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Monday 30 May 2011

Download Turbo C++

Download Turbo C++.....
C++
Download Turbo C++


1) Just extract it.


2) Run .exe


3) Install it like other programs.(Install only in C: Drive)


4) Run Turbo C++ from desktop.


ENJOY....... ^_^

Few best practices for Windows security....


Few best practices for Windows security....that you can do to secure your Windows and data from unwanted attacks by viruses,spywares,etc.
Windows Security Shield
1) Reduce the attack surface whenever possible:-
One of the first steps you should take when hardening a machine is to reduce its attack surface. The more code that's running on a machine, the greater the chance that the code will be exploitable. You should therefore uninstall any unnecessary operating system components and applications.

2) Use only reputable applications:-
Given the current economic climate, it might be tempting to use freeware, deeply discounted, or open source
applications. While I will be the first to admit that I use a handful of such applications in my own organization, it is critically important to do a little bit of research before adopting such an application. Some free or low cost
applications are designed to serve ads to users; others are designed to steal personal information from users or track their Internet browsing habits.

3) Use a normal user account when you can:-
As a best practice, administrators should use normal user accounts when they can. If a malware infection occurs, the malware generally has the same rights as the person who is logged in. So of course that malware could be far more damaging if the person who is logged in has administrative permissions.

4) Create multiple Administrator accounts:-
In the previous section, I discussed the importance of using a regular user account whenever possible and using an Administrative account only when you need to perform an action that requires administrative permissions. However, this does not mean that you should be using the domain Administrator account.
If you have multiple administrators in your organization, you should create a personalized administrator account for each of them. That way, when an administrative action is performed, it is possible to tell who did it. For example, if you have an Administrator named John Doe, you should create two accounts for that user. One will be the normal account for day-to-day use, and the other will be an administrative account to be used only when necessary. The accounts might be named JohnDoe and Admin-JohnDoe.

5) Don't go overboard with audit logging:-
Although it may be tempting to create audit policies that track every possible event, there is such a thing as too much of a good thing. When you perform excessive auditing, the audit logs grow to massive sizes. It can be nearly impossible to find the log entries you're looking for. Rather than audit every possible event, it is better to focus on auditing only the events that matter the most.

6) Make use of local security policies:-
Using Active Directory based group policy settings does not nullify the need for local security policy settings.
Remember that group policy settings are enforced only if someone logs in using a domain account. They do
nothing if someone logs into a machine using a local account. Local security policies can help to protect your
machines against local account usage.

7) Review your firewall configuration:-
You should use a firewall at the network perimeter and on each machine on your network, but that alone isn't
enough. You should also review your firewall's port exceptions list to ensure that only the essential ports are
open.A lot of emphasis is typically placed on the ports that are used by the Windows operating system, but you should also be on the lookout for any firewall rules that open ports 1433 and 1434. These ports are used for monitoring and remotely connecting to SQL server and have become a favorite target for hackers.

8) Practice isolation of services:-
Whenever possible, you should configure your servers so that they perform one specific task. That way, if a
server is compromised, the hacker will gain access to only a specific set of services. I realize that financial
constraints often force organizations to run multiple roles on their servers. In these types of situations, you may
be able to improve security without increasing costs by using virtualization. In certain virtualized environments,
Microsoft allows you to deploy multiple virtual machines running Windows Server 2008 R2 for the cost of a
single server license.

9) Apply security patches in a timely manner:-
You should always test patches before applying them to your production servers. However, some organizations really go overboard with the testing process. While I certainly do not deny the importance of ensuring server stability, you have to balance the need for adequate testing with the need for adequate security.When Microsoft releases a security patch, the patch is designed to address a well-documented vulnerability. This means that hackers already know about the vulnerability and will be specifically looking for deployments in which the patch that corrects that vulnerability has not yet been applied.

10) Make use of the Security Configuration Wizard:-
The Security Configuration Wizard allows you to create XML-based security policies, which can then be applied to your servers. These policies can be used to enable services, configure settings, and set firewall rules. Keep in mind that the policies created by the Security Configuration Wizard are different from security templates (which use .INF files) Furthermore, you can't use group policies to deploy Security Configuration Wizard policies.

*************************

Sunday 29 May 2011

Which DBMS,Database Google is using??....It's Google Bigtable

Which DBMS,Database Google is using??....It's Google Bigtable

Google Bigtable: A Distributed Storage System for Structured Data


Google Bigtable
Bigtable is a distributed storage system for managing structured data that is designed to scale to a very large size: petabytes of data across thousands of commodity servers. Many projects at Google store data in Bigtable, including web indexing, Google Earth, and Google Finance. These applications place very different demands on Bigtable, both in terms of data size (from URLs to web pages to satellite imagery) and latency requirements (from backend bulk processing to real-time data serving). Despite these varied demands, Bigtable has successfully provided a flexible, high-performance solution for all of these Google products.


Some features:-
* Fast and extremely large-scale DBMS.
* A sparse, distributed multi-dimensional sorted map, sharing characteristics of both row-oriented and column-oriented databases.
* Designed to scale into the petabyte range
* It works across hundreds or thousands of machines
* It is easy to add more machines to the system and automatically start taking advantage of those resources without any reconfiguration
* Each table has multiple dimensions (one of which is a field for time, allowing versioning)
* Tables are optimized for GFS (Google File System) by being split into multiple tablets - segments of the table as split along a row chosen such that the tablet will be ~200 megabytes in size.

Architecture:-
BigTable is not a relational database. It does not support joins nor does it support rich SQL-like queries. Each table is a multidimensional sparse map. Tables consist of rows and columns, and each
cell has a time stamp. There can be multiple versions of a cell with different time stamps. The time stamp allows for operations such as "select 'n' versions of this Web page" or "delete cells that are older than a specific date/time."In order to manage the huge tables, Bigtable splits tables at row boundaries and saves them as tablets. A tablet is around 200 MB, and each machine saves about 100 tablets. This setup allows
tablets from a single table to be spread among many servers. It also allows for fine-grained load balancing. If one table is receiving many queries, it can shed other tablets or move the busy table to another machine that is not so busy. Also, if a machine goes down, a tablet may be spread across many other servers so that the performance impact on any given machine is minimal.Tables are stored as immutable SSTables and a tail of logs (one log per machine). When a machine runs out of system memory, it compresses some tablets using Google proprietary compression techniques (BMDiff and Zippy). Minor compactions involve only a few tablets, while major compactions involve the whole table system and recover hard-disk space.The locations of Bigtable tablets are stored in cells. The lookup of any particular tablet is handled by a three-tiered system. The clients get a point to a META0 table, of which there is only one. The META0 table keeps track of many META1 tablets that contain the locations of the tablets being looked up. Both META0 and META1 make heavy use of pre-fetching and caching to minimize bottlenecks in the system.

Implementation:-
BigTable is built on Google File System (GFS), which is used as a backing store for log and data files. GFS provides reliable storage for SSTables, a Google-proprietary file format used to persist table data. Another service that BigTable makes heavy use of is Chubby, a highly-available, reliable distributed lock service. Chubby allows clients to take a lock, possibly associating it with some metadata, which it can renew by sending keep alive messages back to Chubby. The locks are stored in a filesystem-like hierarchical naming structure.
There are three primary server types of interest in the Bigtable system:
* Master servers: assign tablets to tablet servers, keeps track of where tablets are located and redistributes tasks as needed.
* Tablet servers: handle read/write requests for tablets and split tablets when they exceed size limits (usually 100MB - 200MB). If a tablet server fails, then a 100 tablet servers each pickup 1 new tablet and the system recovers.
* Lock servers: instances of the Chubby distributed lock service. Lots of actions within BigTable require acquisition of locks including opening tablets for writing, ensuring that there is no more than one active Master at a time, and access control checking.

API:-
Typical operations to BigTable are creation and deletion of tables and column families, writing data and deleting columns from a row. BigTable provides this functions to application developers in an API. Transactions are supported at the row level, but not across several row keys.

Some common PC File Extension Listing


Some common PC File Extension Listing
This chart is a list of the most commonly found extensions, what type of file they are and what program if any they are associated with.
File Extensions

.$$$ Temporary file
.$$A OS/2 program file
.$$F OS/2 database file
.$$S OS/2 spreadsheet file
.$D$ OS/2 planner file
.$DB DBASE IV temporary file
.$ED Microsoft C temporary editor file.
.$VM Microsoft Windows temporary file for virtual managers.
._DD Norton disk doctor recovery file.
._DM Nuts n Bolts disk minder recovery file.
.--- File used to backup sys, ini, dat, and other important files from Windows 3.1 and above.
.075 Ventura Publisher 75x75 dpi screen characters
.085 Ventura Publisher 85x85 dpi screen characters
.091 Ventura Publisher 91x91 dpi screen characters
.096 Ventura Publisher 96x96 dpi screen characters
.0B Pagemaker printer font LineDraw enhanced characters.
.1ST File used by some software manufacturers to represent a file that should be read first before starting the program.
.2GR File used in Windows 3.x to display the graphics on older 286 and 386 computers.
.386 Virtual machine support files for the 386 enhanced mode.
.3GR File used in Windows 3.x to display the graphics on later 386, 486 and Pentium computers.
.4SW 4DOS Swap file


A
A ADA program file or UNIX library
.A3W MacroMedia Authorware 3.5 file
.ABK Autobackup file used with Corel Draw 6 and above.
.ABR Brush file for Adobe Photoshop
.ACT Adobe Photoshop Color table file.
.AD After Dark file.
.ADF Adapter description files.
.ADM After Dark screen saver module.
.ADR After Dark randomizer
.AI Adobe Illustrator file.
.AIF Auto Interchange File Format (AIFF) Audio file.
.ANI Windows 95 / Windows 98 / Windows NT animated mouse cursor file.
.ANS ANSI text file.
.ARJ Compressed file can be used with Winzip / Pkzip.
.ASC ASCII Text file
.ASF Sort for Advanced Streaming Format, file developed by Microsoft. The .ASF file is generally a movie player and can be open with software such as Windows Media Player.
.ASP Microsoft FrontPage Active Server Pages. To open these files use your internet browser.
.AVI Windows Movie file.


B
.BAK Backup file used for important windows files usually used with the System.ini and the Win.ini.
.BAS QBasic program and or Visual Basic Module.
.BAT Batch file that can perform tasks for you in dos, like a macro.
.BFC Microsoft Windows 95 / Windows 98 Briefcase file.
.BG Backgammon game file.
.BIN Translation tables for code pages other than the standard 437.
.BK2 Word Perfect for Windows Backup file
.BK3 Word Perfect for Windows Backup file
.BK4 Word Perfect for Windows Backup file
.BK5 Word Perfect for Windows Backup file
.BK6 Word Perfect for Windows Backup file
.BK7 Word Perfect for Windows Backup file
.BK8 Word Perfect for Windows Backup file
.BK9 Word Perfect for Windows Backup file
.BMP Graphical Bit Mapped File used in Windows Paintbrush.
.BNK Sim City Backup
.BPS Microsoft Works Word Processor File.
.BPT Corel Draw Bitmap master file
.BV1 Word Perfect for Windows Backup file
.BV2 Word Perfect for Windows Backup file
.BV3 Word Perfect for Windows Backup file
.BV4 Word Perfect for Windows Backup file
.BV5 Word Perfect for Windows Backup file
.BV6 Word Perfect for Windows Backup file
.BV7 Word Perfect for Windows Backup file
.BV8 Word Perfect for Windows Backup file
.BV9 Word Perfect for Windows Backup file
.BWP BatteryWatch pro file.


C
.C C file used with the C programming language.
.CAB Cabinet file used in Windows 95 and Windows 98 that contains all the windows files and drivers. Information about how to extract a .CAB file can be found on document CH000363.
.CAL Windows Calendar, Supercalculator4 file or Supercal spreadsheet.
.CBL COBOL Program File
.CBT Computer Based Training files.
.CDA CD Audio Player Track.
.CDR Corel Draw Vector file.
.CFB Comptons Multimedia file
.CFG Configuration file
.CFL Corel flowchart file
.CFM Corel FontMaster file / Cold Fusion Template file / Visual dBASE windows customer form
.CHK Scandisk file which is used to back up information that scandisk has found to be bad, found in C root. Because the information within these files are corrupted or reported as bad by Scandisk it is perfectly fine to delete these files, providing you are currently not missing any information. Additional information about scandisk can be found on our scandisk page.
.CL Generic LISP source code.
.CL3 Easy CD Creator layout file.
.CL4 Easy CD Creator layout file.
.CLA Java Class file.
.CLG Disk catalog database
.CLK Corel R.A.V.E. animation file.
.CLL Crick software clicker file
.CLO Cloe image
.CLP Windows Clipboard / Quattro Pro clip art / Clipper 5 compiler script
.CLR WinEdit Colorization word list / 1st reader binary color screen image / PhotStyler color definition
.CLS Visual Basic Class module / C++ Class definition
.CMD Windows Script File also OS/2 command file.
.CMV Corel Movie file.
.CNT Help file (.hlp) Contents (and other file contents)
.CPL Windows 95 / Windows 98 / Windows NT control panel icons.
.CNE Configuration file that builds .COM files.
.CNF Configuration file.
.COB COBOL source code file.
.COD FORTRAN Compiler program code
.COM File that can be executed.
.CPE Fax cover page file
.CPI Code Page Information or Microsoft Windows applet control panel file
.CPP C++ source code file.
.CRD Windows Card file.
.CSV Comma-Separated Variable file. Used primary with databases and spreadsheets / Image file used with CopuShow
.CUR Windows Mouse Cursor.
.CVS Canvas drawing file
.CXX C++ program file or Zortech C++ file


D
.DAT Data file, generally associated or extra data for a program to use.
.DB Paradox database file / Progress database file
.DB2 dBase II file
.DBC Microsoft Visiual Foxpro database container
.DBF dBase II,III,III+,IV / LotusWorks database.
.DBK dBase databse backup / Orcad schematic capture backup file
.DBM Cold Fusion template
.DBO dBase IV compiled program file
.DBQ Paradox memo
.DBT dBase database text file
.DBV Flexfile memo field file
.DBW DataBoss database file
.DBX Database file / DataBeam Image / MS Visual Foxpro Table
.DEV Device Driver
.DIF Document Interchange Format; VisiCalc
.DLL Dynamic Link Library; Allow executable code modules to be loaded on demand, linked at run time, and unloaded when not needed. Windows uses these files to support foreign languages and international/nonstandard keyboards.
.DMO Demo file
.DMP Dump file
.DMD Visual dBASE data module
.DMF Delusion/XTracker Digital Music File
.DMO Demo file
.DMP Dump file
.DMS Compressed archive file
.DOC Microsoft Word Windows/DOS / LotusWorks word processor Windows/DOS /PF S:First Choice Windows/DOS DOT MS Word Windows/DOS.
.DOS Text file and DOS Specification Info
.DOT Microsoft Word Template (Macro).
.DRV Device driver files that attach the hardware to Windows. The different drivers are system, keyboard, pointing devices, sound, printer/ plotter, network, communications adapter.
.DRW Micrografx draw/graph files.
.DT_ Macintosh Data File Fork
.DTA Data file
.DTD SGML Document definition file
.DTF Q&A database
.DTM DigiRekker module
.DTP SecurDesk! Desktop / Timeworks Publisher Text Document / Pressworks Template file
.DUN Dialup Networking exported file.
.DX Document Imaging file / Digital data exchange file
.DXB Drawing interchange binary file
.DXF Autocad drawing interchange format file
.DXN Fujitsu dexNet fax document
.DXR Macromedia director projected movie file
.DYN Lotus 1-2-3 file
.DWG AutoCad Drawing Database


E
.EEB Button bar for Equation Editor in Word Perfect for Windows
.EFT CHIWRITER high resolution screen characters
.EGA EGA screen characters for Ventura Publisher
.ELG Event List text file used with Prosa
.EMS Enhanced Menu System configuration file for PC Tools
.EMU IRMA Workstation for Windows emulation
.ENC ADW Knowledge Ware Encyclopedia
.END Corel Draw Arrow Definition file
.ENG Sprint dictionary file engine
.ENV Word Perfect for Windows environment file.
.EPG Exported PaGe file used with DynaVox
.EPS Encapsulated Postscript, with embedded TIFF preview images.
.EQN Word Perfect for Windows Equation file
.ERD Entity Relation Diagram graphic file
.ERM Entity Relation Diagram model file
.ERR Error log file
.ESH Extended Shell Batch file
.EVT Event file scheduler file for PC Tools
.EX3 Device driver for Harvard graphics 3.0
.EXC QEMM exclude file from optimization file or Rexx program file
.EXE Executable file.
.EXT Extension file for Norton Commander


F
.FDF Adobe Acrobat Forms Document.
.FF AGFA CompuGraphics outline font description.
.FFA Microsoft Fast Find file.
.FFF GUS PnP bank / defFax fax document
.FFL Microsoft Fast Find file / PrintMaster Gold form file
.FFO Microsoft Fast Find file
.FFT DCA/FFT final form text
.FFX Microsoft Fast Find file
.FON Font files to support display and output devices.
.FR3 dBase IV renamed dBase III+ form
.FRF FontMonger Font
.FRG dBase IV uncompiled report
.FRK Compressed zip file used with Apple Macinotsh computers.
.FRM Form file used with various programs / Microsoft Visual Basic Form / FrameMaker document / FrameBuilder file / Oracle executable form / Word Perfect Merge form / DataCAD symbol report file
.FRO dBase IV compiled report / FormFlow file
.FRP PerForm Pro Plus Form
.FRS WordPerfect graphics driver
.FRT FoxPro report file
.FRX Microsoft Visual basic binary form file / FoxPro report file
.FRZ FormFlow file


G
.GIF CompuServe Graphics Interchange Format.
.GR2 286 grabbers that specify which font to use with DOS and Windows.
.GR3 386 grabbers that specify which font to use with DOS and Windows.
.GRA Microsoft Flight simulator graphics file
.GRB Microsoft MS-DOS shell monitor
.GRF Micrografx draw/graph files.
.GRP Microsoft Program Group.
.GZ Compressed Archive file for GZip


H
.HBK Mathcad handbook file
.HDL Procomm Plus alternate download file listing
.HDR Procomm Plus message header
.HDX Help index
.HEX Hex dump
.HFI GEM HP font info
.HGL HP graphics language graphic
.HH C++ Header
.HHH Precompiled Header for Power C
.HHP Help data for Procomm Plus
.HLP Files that contain the Help feature used in windows, cannot be read from DOS.
.HQX Apple Macintosh Binhex text conversion file.
.HSQ Data files associated with the Qaz Trojan.
.HSS Photoshop Hue/Saturation information.
.HST History file / Procomm Plus History File / Host file.
.HTA Hypertext Application (run applications from HTML document).
.HTM Web page files containing HTML or other information found on the Internet.


I
.ICA Citrix file / IOCA graphics file
.ICB Targa Bitmap
.ICC Kodak printer image
.ICE Archive file
.ICL Icon library file
.ICM Image Color Matching profile file
.ICN Microsoft Windows Icon Manager.
.ICO Microsoft Windows Icondraw / Icon.
.ID Disk identification file.
.IDB Microsoft developer intermediate file, used with Microsoft Visual Studio
.IDD MIDI instruments definition
.IDE Integrated Development Environment configuration file
.IDF MIDI instruments drivers file
.IDQ Internet data query file
.IDX Index file
.IFF IFF/LBM (Amiga) used by Computer Eyes frame grabber.
.IMG GEM/IMG (Digital Research) or Ventura Publisher bitmap graphic
.INF Information file that contains customization options.
.INI Files that initialize Windows and Windows apps.
.IPF Installer Script File / OS/2 online documentation for Microsoft source files.
.ISO Compressed file used for an exact duplicate of a CD. .ISO files can be extracted or opened such programs as Win Image that can be found on our shareware download section.
.IWA IBM Writing Assistant Text file.


J
.JAS Graphic
.JPG Graphic commonly used on the Internet and capable of being opened by most modern image editors.
.JS JavaScript file.
.JSB Henter-Joyce Jaws script binary file
.JSD eFAX jet suite document
.JSE JScript encoded script file
.JSH Henter-Joyce Jaws script header file
.JSL PaintShop pro file
.JSM Henter-Joyce Jaws script message file
.JSP Java server page
.JSS Henter-Joyce Jaws script source file
.JT JT fax file
.JTF JPEG tagged Interchange format file
.JTK Sun Java toolkit file
.JTP JetForm file
.JW Justwrite text file
.JWL Justwrite text file library
.JZZ Jazz spreadsheet


K
.KAR Karaoke File used with some audio players.


L
.LGC Program Use Log File (for Windows Program Use Optimization).
.LGO Contains the code for displaying the screen logo.
.LOG Contains the process of certain steps, such as when running scandisk it will usually keep a scandisk.log of what occurred.
.LNK HTML link file used with Microsoft Internet Explorer.
.LWP Lotus Wordpro 96/97 file.


M
.MAC Macintosh macpaint files.
.MBX Microsoft Outlook Express mailbox file.
.MD Compressed Archive file
.MDA Microsoft Access Add-in / Microsoft Access 2 Workgroup.
.MDB Microsoft Access Database / Microsoft Access Application.
.MDE Microsoft Access Database File
.MDF Menu definition file
.MDL Digitrakker Music Module / Rational Rose / Quake model file
.MDM Telix Modem Definition
.MDN Microsoft Access Blank Database Template
.MDP Microsoft Developer Studio Project
.MDT Microsoft Access Add-in Data
.MDW Microsoft Access Workgroup Information
.MDX dBase IV Multiple Index
.MDZ Microsoft Access Wizard Template
.MEB WordPerfect Macro Editor bottom overflow file
.MED WordPerfect Macro Editor delete save / OctaMed tracker module
.MEM WordPerfect Macro Editor macro / Memory File of variables
.MID Midi orchestra files that are used to play with midi sounds built within the sound card.
.MIX Power C object file / Multiplayer Picture file (Microsoft Photodraw 2000 & Microsoft Picture It!) / Command & Conquer Movie/Sound file
.MOD Winoldap files that support (with grabbers) data exchange between DOS apps and Windows apps.
.MOV File used with Quick Time to display a move.
.MP1 MPEG audio stream, layer I
.MP2 MPEG audio stream, layer II
.MP3 MPEG audio stream, layer III; High compressed audio files generally used to record audio tracks and store them in a decent sized file available for playback. See our MP3 page for additional information.
.MPG MPEG movie file.
.MSN Microsoft Network document / Decent mission file
.MTF Windows metafile.
.MTH Derive Math file
.MTM Sound file / MultiTracker music module
.MTV Picture file
.MTW Minitab data file
.MU Quattro menu
.MUL Ultima Online game
.MUP Music publisher file
.MUS Audio file
.MVB Database file / Microsoft multimedia viewer file
.MVE Interplay video file
.MVF Movie stop frame file
.MWP Lotus Wordpro 97 smartmaster file
.MXD ArcInfo map file
.MXT Microsoft C Datafile
.MYD Make your point presentation file.


N
.N64 Nintendo 64 Emulator ROM image.
.NA2 Netscape Communicator address book.
.NAB Novell Groupwise address book
.NAP Napster Music security definition file.
.NDF NeoPlanet Browser file
.NDX Indexed file for most databases.
.NES Nintendo Entertainment system ROM image.
.NIL Norton guide online documentation
.NGF Enterasys Networks NetSight file.
.NHF Nero HFS-CD compilation or a general Nero file
.NIL Norton icon lybrary file.
.NLB Oracle 7 data file
.NLD ATI Radeon video driver file,
.NMI SwordSearcher file.
.NON LucasArts Star Wars - Tie fighter mouse options file.
.NOW Extension commonly used for readme text files.
.NRA Nero Audio CD file.
.NRB Nero CD-ROM boot file.
.NS2 Lotus Notes 2 database,
.NS5 Lotus Notes Domino file,
.NSO NetStudio easy web graphics file.
.NT Windows NT startup file.
.NUM File used with some Software Manufactures to store technical support numbers or other phone numbers, should be readable from DOS and or Windows.


O
.OCA Control Typelib Cache.
.OCX Object Linking and Embedding (OLE) control extension.
.OLB Object library
.OLD Used for backups of important files incase they are improperly updated or deleted.
.OLE Object Linking and Embedding object file
.OLI Olivetti text file
.ORI Original file.


P
.PAB Personal Address Book, file used with Microsoft Outlook.
.PB WinFax Pro phone book file
.PBD PowerBuilder dynamic library / Faxit phone book file
.PBF Turtle Beach Pinnacle bank file
.PBK Microsoft phonebook file
.PBL PowerBuilder library file
.PBM UNIX portable bitmap fuke
.PBR PowerBuilder resource
.PBI Profiler binary input file
.PBM PBM portable bit map graphic
.PBO Profiler binary output
.PBT Profiler binary table
.PCX Microsoft Paint & PC Paintbrush Windows/DOS.
.PDA Bitmap graphic file
.PDB TACT data file
.PDD Adobe PhotoDeluxe Image.
.PDF Adobe Acrobat Reader file which can only be read by Adobe Acrobat (to get file downloaded Adobe Acrobat from our Download Page.
.PDL Borland C++ project description language file.
.PDS Graphic file / Pldasm source code file.
.PDV Paintbrush printer driver.
.PDW Professional Draw document.
.PIC Picture / Viewer Frame Class.
.PIF Program Information File that configures a DOS app to run efficiently in windows.
.PJF Paintjet soft font file.
.PL Harvard palette file / PERL program file
.PL3 Harvard chart palette
.PLB Foxpro library / LogoShow Screensaver file
.PLC Lotus Add-in
.PLD PLD2 source file
.PLG REND386 / AVRIL file
.PLI Oracle 7 data description
.PLL Prelinked library
.PLM DisorderTracker2 module
.PLN WordPerfect spreadsheet file
.PLR Descent Pilot file
.PLS WinAmp MPEG playlist file / DisorderTracker 2 Sample file / Shoutcast file / MYOB data file
.PLT AutoCAD HPGL vector graphic plotter file / Gerber sign-making software file / Betley's CAD Microstation driver configuration for plotting
.PLY Autodesk polygon
.PP Compressed archive file.
.PP4 Picture Publisher.
.PP5 Picture Publisher.
.PPA Power Point Add-in.
.PPB WordPerfect Print preview button bar.
.PPD PostScript Printer description.
.PPF Turtle Beach Pinnacle program file.
.PPI Microsoft PowerPoint graphic file.
.PPL Harvard (now Serif) Polaroid Palette Plus ColorKey Driver.
.PPM PBM Portable Pixelmap Graphic.
.PPO Clipper Preprocessor Output.
.PPP Serif PagePlus Publication.
.PPS Microsoft PowerPoint Slideshow.
.PPT Microsoft PowerPoint presentation.
.PPX Serif PagePlus publication.
.PPZ Microsoft PowerPoint Packaged Presentation.
.PS2 File to support the Micro Channel Architecture in 386 Enhanced mode.
.PSD Adobe Photoshop image file.
.PST Post Office Box file used with Microsoft Outlook usually mailbox.pst unless named otherwise.
.PWA Password agent file.
.PWD Password file.
.PWF ProCite Workforms
.PWL Password file used in Windows 95 and Windows 98 is stored in the Windows directory.
.PWP Photoworks image file
.PWZ PowerPoint wizard


Q
.QIC Windows backup file
.QT Quick Time Movie File
.QXD Quark Express file
.QXL Quark Xpress element library
.QXT Quark Xpress template file


R
.RA Real Audio file.
.RAM Real Audio file.
.RAR Compressed file similar to .ZIP uses different compression program to extract. See our recommended download page for a program that can be used to extract .RAR files.
.RAS File extension used for raster graphic files.
.RD1 Descent registered level file
.RD3 Ray Dream designer graphics file / CorelDraw 3D file
.RD4 Ray Dream designer graphics file
.RD5 Ray Dream designer graphics file
.RDB TrueVector rules database
.RDF Resource description framework file / Chromeleon report definition
.RDL Descent registered level file / RadioDestiny radio stream
.RDX Reflex data file
.REC Sound file used with Windows Sound Recorder.
.RLE Microsoft Windows Run Length Encoded (Run Length Encoded (bitmap format) file that contains the actual screen logo).
.RMI Microsoft RMID sound file.
.RPB Automotive diagnostic file.
.RPD Rapidfile database
.RPM Red Hat Package Manager / RealMedia Player file.
.RPT Various Report file
.RTF Rich Text Format file
.RWZ Microsoft Outlook rules wizard file


S
.SAV File that usually contains saved information such as a saved game.
.SC2 Maps used in Sim City 2000.
.SCP Dialup Networking script file.
.SCR Source files for the .INI files, or sometimes may be used as screen savers.
.SD Sound Designer I audio file
.SD2 Sound Designer II flattened file / Sound Designer II data fork file / SAS database file
.SDA StarOffice drawing file / SoftCuisine data archive
.SDC StarOffice spreadsheet
.SDD StarOffice presentation
.SDF Standard data format file / Schedule data file / System file format / Autodesk mapguide spatial data file
.SDK Roland S-series floppy disk image
.SDL SmartDraw library
.SDN Small archive
.SDR SmartDraw drawing
.SDS StarOffice chart file / Raw MIDI sample dump standard file
.SDT SmartDraw template
.SDV Semicolon divided value file
.SDW Sun Microsystems StarOffice file document file similar to the Microsoft Office .DOC file.
.SDX MIDI sample dump standard files compacted by SDX
.SEA Short for Self Extracting Archive. Compressed file used with the Macintosh.
.SH Archive file
.SH3 Harvard (now Serif) presentation file
.SHB Corel Background file
.SHG Hotspot Editor Hypergraphic
.SHK Macintosh Compressed Archive file
.SHM WordPerfect Shell Macro
.SHP 3D Studio Shapes File / other 3D related file
.SHR Archive file
.SHS Shell scrap object file
.SHW Corel presentation / WordPerfect Slide Show / Show File
.SLK Multiplan file.
.SND Sound Clip file / Raw unsigned PCM data / AKAI MPC-series sample / NeXT sound / Macintosh sound resource file
.SNG MIDI song
.SNM Netscape Mail
.SNO SNOBOL program file
.SNP Snapview snapshot file
.SUM Summary file.
.SWF Macromedia Flash file.
.SWP Extension used for the Windows Swap File usually Win386.Swp. This file is required by Windows and generally can grow very large in size sometimes up to several hundred megs. This file is used to swap information between currently running programs and or memory. If this file is deleted from the computer Windows will be unable to load and will need to be reinstalled.
.SYS System and peripheral drivers.


T
.TDF Trace Definition File used with OS/2
.TGA Targa file
.TIF Tag Image Format that includes most 24-bit color.
.TLB Remote automation truelib files / OLE type library / Visual C++ type library
.TLD Tellix file
.TLE NASA two-line element set
.TLP Microsoft project timeline fie
.TLT Trellix web design file
.TLX Trellix data file
.TMP Temporary files.
.TRM Windows Terminal.
.TXT Text file that can be read from windows of from DOS by using the Edit, Type, or Edlin.


U
.UNI MikMod (UniMod) format file / Forcast Pro data file
.UNK Unknown file type, sometimes used when a file is received that cannot be identified
.UNX Text file generally associated with UNIX.
.URL File used with some browsers such as Internet Explorer linking you to different web pages. Internet Shortcut.


V
.VB VBScript file
.VBA vBase file
.VBD ActiveX file
.VBE VBScript encoded script file
.VBG Visual Basic group project file
.VBK VisualCADD backup file
.VBL User license control file
.VBP Visual Basic project file
.VBR Remote automation registration files
.VBS Microsoft Visual Basic Script file for quick programs and in some cases can be used as a virus file.
.VBW Visual Basic project workplace
.VBX Visual Basic extension file
.VBZ Wizard launch file
.VC VisiCalc Spreadsheet file.
.VCD VisualCADD Drawing file.
.VCE Natural MicroSystems voice file.
.VCF vCard File / Vevi Configuration file.
.VCS Microsoft Outlook vCalander file.
.VCT FoxPro class library.
.VCW Microsoft Visual C++ workbench information file.
.VCX FoxPro class library.
.VDA Targa bitmap
.VDD Short for Virtual Device Driver. Additional information can be found here.
.VDO VDOScript file
.VDX No such file extension - Likely you meant to .vxd
.VM Virtual Machine / Virtual Memory file.
.VMM Virtual Machine (Memory Manager) file.
.VMF Ventura font characteristics file / FaxWorks audio file
.VMH
.VS2 Roland-Bass transfer file.
.VSD Visio drawing.
.VSL GetRight download list file.
.VSS Visio stencil.
.VST Video Template / Truevision Vista graphic / Targa Bitmap/
.VSW Visio workspace file.
.VXD Windows system driver file allowing a driver direct access to the Windows Kernel, allowing for low level access to hardware.


W
.WAB Microsoft Outlook Express personal address book.
.WAD File first found in IdSoftware games such as DOOM, Quake, as well as most new games similar to these.
.WAV Sound files in Windows open and played with sound recorder.
.WB1 Quattro Pro Notebook
.WB2 Quattro Pro Spreadsheet
.WBF Microsoft Windows Batch File
.WBK Wordperfect document / workbook
.WBT Winbatch batch file
.WCD Wordperfect macro token list
.WCM Microsoft Works data transmission file / Wordperfect Macro
.WCP Wordperfect product information description
.WDB Microsoft Works database
.WEB Web source code file
.WFM dBASE Form object
.WFN CorelDRAW font
.WFX Winfax data file
.WG1 Lotus 1-2-3 worksheet
.WG2 Lotus 1-2-3 for OS/2 worksheet
.WID Ventura publisher width table
.WIN Foxpro - dBASE window file
.WIZ Microsoft Publisher page wizard
.WK1 Lotus 1-2-3 all versions / LotusWorks spreadsheet.
.WK3 Lotus 1-2-3 for Windows /Lotus 1-2-3 Rel.3.
.WKS Lotus 1-2-3 Rel lA,2.0,2.01, also file used with Microsoft Works.
.WLG Dr. Watson log file.
.WMA Windows Media Audio file.
.WMF Windows Metafile. Also see WMF dictionary definition.
.WMZ Windows Media Player theme package file.
.WPD WordPerfect Windows/DOS.
.WPG WordPerfect Graphical files Windows/DOS.
.WPM WordPerfect Macro file.
.WPS MS Works word processor Windows/DOS.
.WRI Windows Write.
.WRK Lotus 1-2 31.0,1.01,1.1/ Symphony 1,1.01.
.WRI Symphony l.1,1.2,2 / Microsoft Write file.


X
.XIF Wang image file / Xerox image file
.XLB Microsoft Excel File.
.XLS Microsoft Excel File.
.XM Sound file / Fast tracker 2 extended module
.XML Extensible markup language file.
.XNK Exchange shortcut
.XOT Xnetech job output file
.XPM X picsmap graphic
.XQT SuperCalc macro sheet
.XRF Cross Reference
.XR1 Epic MegaGames Xargon File
.XSL XML Style sheet
.XSM LEXIS-NEXIS tracker
.XTB LocoScript external translation table
.XWD X Windows dump file
.XWF Yamaha XG Works file
.XXE Xxencoded file
.XY XYWrite text file
.XY3 XYWrite text file
.XY4 XYwrite IV document
.XYP XYwrite III plus document
.XYW XYwrite Windows 4.0 document


Y
.Y Amiga YABBA compressed file archive
.Y01 Paradox index file
.Y02 Paradox index file
.Y03 Paradox index file
.Y04 Paradox index file
.Y05 Paradox index file
.Y06 Paradox index file
.Y07 Paradox index file
.Y08 Paradox index file
.Y09 Paradox index file
.YUV Yuv graphics file
.YZ YAC compressed file archive.


Z
.Z Compressed file that can hold thousands of files. To extract all the files Pkzip or Winzip will need to be used. UNIX / Linux users use the compress / uncompress command to extract these files.
.ZIP Compressed file that can hold thousands of files. To extract all the files Pkzip or Winzip will need to be used.

Saturday 28 May 2011

Hack Windows XP Start Button - How to change Windows XP Start Button appearance


Hack Windows XP Start Button - How to change Windows XP Start Button appearance

Change the Start text:-
1. First of all, make sure you download Resource Hacker. You'll need this puppy to edit resources inside your Windows shell.

2. Locate explorer.exe in your c:\Windows directory. Make a copy of the file in the same directory and rename it explorer.bak.

3. Now launch Resource Hacker. In the File menu, open explorer.exe. You'll now see a bunch of collapsed folders.

4. Expand the String Table folder and then find folder No. 37 (folder No. 38 if you're in Windows Classic mode).

5. Click on resource 1033 and locate the text that says "Start." This is your Start button, and now you've got control over what it says! Change the "Start" text to your text of choice. You don't have a character limit, but the text takes up valuable taskbar space, so don't make it too long.

6. Click on the button labeled Compile Script. This updates the settings for your Start button. But nothing will happen until you complete through step #20, so keep going!


Change your hover text:-
7. While you're here, why not also change the text that pops up when your mouse hovers over your Start button?

8. Right now it says "Click here to begin." Well, duh! We already know that's where to begin!

9. Open folder No. 34 and click on resource 1033.

10. Find the text that says "Click here to begin" and change it to something cooler. Might I suggest "Open It."

11. Click on the Compile Script button to update this resource.


Customize your Start icon:-
12. For an added bonus, you can also change the Windows icon to the left of the text, too.

13. Collapse the String Table folder and expand the Bitmap folder at the top of your folder list.

14. Click on folder No. 143 and click on resource 1033. You should see that familiar Windows icon.

15. Go to the Action Menu and select "Replace bitmap." Select "Open file with new bitmap", and locate the replacement image on your machine. Note: The image must have a .bmp extension and a size of 25 pixels by 20 pixels. Then click the Replace button.

16. Now that you've made your changes, save the file in your Windows folder with another name, such as newstartbutton.exe. Don't name it Explorer.exe, because that file is already being used by your system. Close all open programs and restart your system.

17. Boot into Safe Mode With Command Prompt by pressing F8 on startup. Then choose Safe Mode in the command prompt.

18. Log on as administrator and enter your password.

19. When the command prompt comes up, make sure you're in the right directory by typing "cd c:\windows" (without the quotes).

20. Now type "copy c:\windows\newstartbutton.exe c:\windows\explorer.exe" (no quotes). Type "yes" (no quotes) to overwrite the existing file, then restart your system by typing "shutdown -r" (no quotes).

When Windows relaunches, you'll see your new Start button in all its glory! ^_^

*********************

Friday 27 May 2011

General Keyboard Shortcuts


General Keyboard Shortcuts......
Keyboard Shortcuts
General Keyboard Shortcuts:-

CTRL+C (Copy)

CTRL+X (Cut)

CTRL+V (Paste)

CTRL+Z (Undo)

DELETE (Delete)

SHIFT+DELETE (Delete the selected item permanently without placing the item in the Recycle Bin)

CTRL while dragging an item (Copy the selected item)

CTRL+SHIFT while dragging an item (Create a shortcut to the selected item)

F2 key (Rename the selected item)

CTRL+RIGHT ARROW (Move the insertion point to the beginning of the next word)

CTRL+LEFT ARROW (Move the insertion point to the beginning of the previous word)

CTRL+DOWN ARROW (Move the insertion point to the beginning of the next paragraph)

CTRL+UP ARROW (Move the insertion point to the beginning of the previous paragraph)

CTRL+SHIFT with any of the arrow keys (Highlight a block of text)

SHIFT with any of the arrow keys (Select more than one item in a window or on the desktop, or select text in a document)

CTRL+A (Select all)

F3 key (Search for a file or a folder)

ALT+ENTER (View the properties for the selected item)

ALT+F4 (Close the active item, or quit the active program)

ALT+ENTER (Display the properties of the selected object)

ALT+SPACEBAR (Open the shortcut menu for the active window)

CTRL+F4 (Close the active document in programs that enable you to have multiple documents open simultaneously)

ALT+TAB (Switch between the open items)

ALT+ESC (Cycle through items in the order that they had been opened)

F6 key (Cycle through the screen elements in a window or on the desktop)

F4 key (Display the Address bar list in My Computer or Windows Explorer)

SHIFT+F10 (Display the shortcut menu for the selected item)

ALT+SPACEBAR (Display the System menu for the active window)

CTRL+ESC (Display the Start menu)

ALT+Underlined letter in a menu name (Display the corresponding menu)

Underlined letter in a command name on an open menu (Perform the corresponding command)

F10 key (Activate the menu bar in the active program)

RIGHT ARROW (Open the next menu to the right, or open a submenu)

LEFT ARROW (Open the next menu to the left, or close a submenu)

F5 key (Update the active window)

BACKSPACE (View the folder one level up in My Computer or Windows Explorer)

ESC (Cancel the current task)

SHIFT when you insert a CD-ROM into the CD-ROM drive (Prevent the CD-ROM from automatically playing)

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Dialog Box Keyboard Shortcuts:-

CTRL+TAB (Move forward through the tabs)

CTRL+SHIFT+TAB (Move backward through the tabs)

TAB (Move forward through the options)

SHIFT+TAB (Move backward through the options)

ALT+Underlined letter (Perform the corresponding command or select the corresponding option)

ENTER (Perform the command for the active option or button)

SPACEBAR (Select or clear the check box if the active option is a check box)

Arrow keys (Select a button if the active option is a group of option buttons)

F1 key (Display Help)

F4 key (Display the items in the active list)

BACKSPACE (Open a folder one level up if a folder is selected in the Save As or Open dialog box)

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Microsoft Natural Keyboard Shortcuts:-


Windows Logo (Display or hide the Start menu)

Windows Logo+BREAK (Display the System Properties dialog box)

Windows Logo+D (Display the desktop)

Windows Logo+M (Minimize all of the windows)

Windows Logo+SHIFT+M (Restore the minimized windows)

Windows Logo+E (Open My Computer)

Windows Logo+F (Search for a file or a folder)

CTRL+Windows Logo+F (Search for computers)

Windows Logo+F1 (Display Windows Help)

Windows Logo+ L (Lock the keyboard)

Windows Logo+R (Open the Run dialog box)

Windows Logo+U (Open Utility Manager)

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Accessibility Keyboard Shortcuts:-


Right SHIFT for eight seconds (Switch FilterKeys either on or off)

Left ALT+left SHIFT+PRINT SCREEN (Switch High Contrast either on or off)

Left ALT+left SHIFT+NUM LOCK (Switch the MouseKeys either on or off)

SHIFT five times (Switch the StickyKeys either on or off)

NUM LOCK for five seconds (Switch the ToggleKeys either on or off)

Windows Logo +U (Open Utility Manager)

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Windows Explorer Keyboard Shortcuts:-

END (Display the bottom of the active window)

HOME (Display the top of the active window)

NUM LOCK+Asterisk sign (*) (Display all of the subfolders that are under the selected folder)

NUM LOCK+Plus sign (+) (Display the contents of the selected folder)

NUM LOCK+Minus sign (-) (Collapse the selected folder)

LEFT ARROW (Collapse the current selection if it is expanded, or select the parent folder)

RIGHT ARROW (Display the current selection if it is collapsed, or select the first subfolder)

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Shortcut Keys for Character Map
After you double-click a character on the grid of characters, you can move through the grid by using the keyboard shortcuts:-


RIGHT ARROW (Move to the right or to the beginning of the next line)

LEFT ARROW (Move to the left or to the end of the previous line)

UP ARROW (Move up one row)

DOWN ARROW (Move down one row)

PAGE UP (Move up one screen at a time)

PAGE DOWN (Move down one screen at a time)

HOME (Move to the beginning of the line)

END (Move to the end of the line)

CTRL+HOME (Move to the first character)

CTRL+END (Move to the last character)

SPACEBAR (Switch between Enlarged and Normal mode when a character is selected)

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Microsoft Management Console (MMC) Main Window Keyboard Shortcuts:-


CTRL+O (Open a saved console)

CTRL+N (Open a new console)

CTRL+S (Save the open console)

CTRL+M (Add or remove a console item)

CTRL+W (Open a new window)

F5 key (Update the content of all console windows)

ALT+SPACEBAR (Display the MMC window menu)

ALT+F4 (Close the console)

ALT+A (Display the Action menu)

ALT+V (Display the View menu)

ALT+F (Display the File menu)

ALT+O (Display the Favorites menu)

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MMC Console Window Keyboard Shortcuts:-


CTRL+P (Print the current page or active pane)

ALT+Minus sign (-) (Display the window menu for the active console window)

SHIFT+F10 (Display the Action shortcut menu for the selected item)

F1 key (Open the Help topic, if any, for the selected item)

F5 key (Update the content of all console windows)

CTRL+F10 (Maximize the active console window)

CTRL+F5 (Restore the active console window)

ALT+ENTER (Display the Properties dialog box, if any, for the selected item)

F2 key (Rename the selected item)

CTRL+F4 (Close the active console window. When a console has only one console window, this shortcut closes the console)

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Remote Desktop Connection Navigation:-


CTRL+ALT+END (Open the Microsoft Windows NT Security dialog box)

ALT+PAGE UP (Switch between programs from left to right)

ALT+PAGE DOWN (Switch between programs from right to left)

ALT+INSERT (Cycle through the programs in most recently used order)

ALT+HOME (Display the Start menu)

CTRL+ALT+BREAK (Switch the client computer between a window and a full screen)

ALT+DELETE (Display the Windows menu)

CTRL+ALT+Minus sign (-) (Place a snapshot of the active window in the client on the Terminal server clipboard and provide the same functionality as pressing PRINT SCREEN on a local computer.)

CTRL+ALT+Plus sign (+) (Place a snapshot of the entire client window area on the Terminal server clipboard and provide the same functionality as pressing ALT+PRINT SCREEN on a local computer.)

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Microsoft Internet Explorer Navigation:-


CTRL+B (Open the Organize Favorites dialog box)

CTRL+E (Open the Search bar)

CTRL+F (Start the Find utility)

CTRL+H (Open the History bar)

CTRL+I (Open the Favorites bar)

CTRL+L (Open the Open dialog box)

CTRL+N (Start another instance of the browser with the same Web address)

CTRL+O (Open the Open dialog box, the same as CTRL+L)

CTRL+P (Open the Print dialog box)

CTRL+R (Update the current Web page)

CTRL+W (Close the current window)

******************

Thursday 26 May 2011

Procedure Oriented Programming(POP) vs Object Oriented Programming(OOP)

Procedure Oriented Programming (POP) :-

Conventional programming using high level languages such as COBOL,FORTRAN and C, is commonly known as procedure oriented programming(POP). In the procedure oriented approach, the problem is viewed as a sequence of things to be done such as reading, calculating and printing. A number of functions are written to accomplish these tasks. The primary focus is on functions.
Typical structure of procedure oriented programs
Procedure oriented programming basically consists of writing a list of instructions(or actions) for the computer to follow, and organizing these instructions into groups known as functions.While we concentrate on the development , very little attention is given to the data that are bing used by various functions.

In a multi-function program, many important data items are placed as global so that they may be accessed by all functions. Each function may have its own local data. Global data are more vulnerable to an inadvertent change by a function. In a large program it is very difficult to identify what data is used by which function. In case we need to revise an external data structure, we also need to revise all functions that access the data. This provides an opportunity for bugs to creep in.
Relationship of data and functions in procedural programming
Another serious drawback with the procedural approach is that it does not model real world problems very well. This is because functions are action-oriented and do not really correspond to the elements of the problem.

Some characteristics of Procedure Oriented Programming are :-

1) Emphasis is on doing things(algorithms).
2) Large programs are divided into smaller programs known as functions.
3) Most of the functions share global data.
4) Data more openly around the system from function to function.
5) Functions transform data from one form to another.
6) Employs top-down approach in program design.

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Object Oriented Programming (OOP) :-

The major motivating factor in the invention of object oriented is to remove some of the flaws encountered in the procedural oriented approach. Object oriented programming treats data as a critical element in the program development and does not allow it to flow freely around the system. It ties data more closely to the functions that operate on it, and protects it from accidental modifications from outside functions.

Object oriented programming allows a decomposition of a problem into a number entities called objects and then builds data and functions around these objects. The data of an object can be accessed only by the functions associated with that object. However, functions of one object can access the functions of other objects.
Organization of data and functions in object oriented programming
The object oriented programming can be defined as an " approach that provides a way of modularizing programs by creating partitioned memory area for both data and functions that can be used as templates for creating copies of such modules on demand ". Thus, an object is considered to be a partitioned area of computer memory that stores data and set of operations that can access that data. Since the memory partitions are independent, the objects can be used in a variety of different programs without modifications.

Some characteristics of Object Oriented Programming are :-

1) Emphasis is on data rather than procedures or algorithms.
2) Programs are divided into what are known as objects.
3) Data structures are designed such that characterize the objects.
4) Functions that operate on the data are tied together in the data structure.
5) Data is hidden and cannot be accessed by external functions.
6) Objects may communicate with each other through functions.
7) New data and functions can be easily added whenever necessary.
8) Follows bottom-up approach in program design.

------------------------------------------------------------------------------------------------------------

Benefits of Object Oriented Programming over Procedure Oriented Programming :-

1) Through inheritance, we can eliminate redundant code and extend the use of existing classes which is not possible in procedure oriented approach.

2) We can build programs from the standard working modules that communicate with one another, rather than having to start writing the code from scratch which happens procedure oriented approach. This leads to saving of development time and higher productivity.

3) The principle of data hiding helps the programmer to build secure programs that cannot be invaded by code in other parts of the program.

4) It is possible to have multiple instances of object to co-exist without any interference.

5) It is possible to map objects in the problem domain to those in the program.

6) It is easy to partition the work in a project based on objects .

6) The data-centered design approach enables us to capture more details of a model in implementable from.

7) Object oriented systems can be easily upgraded from small to large systems.

8) Message passing techniques for communication between objects makes the interface descriptions with external systems much simpler.

9) Software complexity can be easily managed.

*************

Wednesday 25 May 2011

Google Chromebook, The cloud computing Laptop


Google has been successful with the Android operating system which is now the Android operating system has become the biggest OS smartphones in the world, Google again broke new ground by trying to offer a new type of concept laptop with the release of Chromebook.

Google Chromebook
Chromebook is the concept of cloud computing platform-based laptops. All required application can be accessed directly from the Internet. All data is also stored in the cloud service so users do not need to worry if the laptop is lost or stolen. Stay replace a new laptop, all applications and data remain secure as before.

"The core of this Chromebook laptop is a Chrome browser," wrote Linus Upson, Vice President of Engineering, and Sundar Pichai, Senior Vice President of Chrome as quoted by the official Google blog. Because applications collected in the cloud, if you need a live search and click to access it. Chromebook already equipped internet access 3G to connect to the internet anytime and anywhere. Because no operating system in general use laptops now, when booting claimed much faster. To access the web or e-mail, can be done in a matter of 8 seconds since the laptop is turned on. The durability of the batteries were up to all day so that users do not need to go back and forth refilling. In addition, the application used will always be updated if there is the latest version so that users get a better experience.

Chromebook name announced in the event Google I / O which brings about 5,000 developers in San Francisco, United States, on Wednesday, May 11, 2011. On the occasion, Google announced two partner manufacturers who are ready to release hardware Chromebook, namely Acer and Samsung. Chromebook will be available online starting June 15 in the U.S., Britain, France, Germany, Holland, Italy, and Spain. Other countries will follow a few months away.

Samsung and Acer Chromebook
Specifications of the Samsung Chromebook:-
- 12.1 "(1280x800) 300 nit display
Samsung Chromebook
- 3:26 lbs / kg 1:48
- 8.5 hours of continuous usage
- Intel ® Dual-Core Processor AtomTM
- Built in dual-band Wi-Fi and World-mode 3G (optional)
- HD Webcam with noise canceling microphone
- 2 USB 2.0 ports 4-in-1 memory card slot
- Mini-VGA port
- Oversize Chrome fullsize keyboard fully-clickable trackpad




Specifications of Acer Chromebook:-
- 11.6 "HD widescreen LED-backlit LCD CineCrystalTM
- 2.95 lbs. 1:34 kg.
- 6 hours of continuous usage
- Intel ® Dual-Core Processor AtomTM
- Built in dual-band Wi-Fi and World-mode 3G (optional)
Acer Chromebook
- HD Webcam with noise canceling microphone
- High-Definition Audio Support
- 2 USB 2.0 ports 4-in-1 memory card slot
- HDMI port
- Oversize Chrome fullsize keyboard fully-clickable trackpad




------------------------------------------------------------------

LG Optimus Black P970


With Nova display technology, screen LG Optimus Black P970 full touch screen mobile phone design is said to be able to present a better view when taken outdoors. Energy consumption also claimed 50% more efficient than the kinds of regular LCDs.
LG Optimus Black P970 is equipped with two cameras, 5 megapixel camera to the back while 2 megapixel camera to the front and claimed to be the first in the world. Indeed the average smartphone today still use 1.3 megapixel camera on the front.
Just as the LG Optimus Big, LG Black Optimus use 1 Ghz processor with OMAP 3630 chipset, which of course it is enough for a smartphone with 4.0-inch screen display.
LG Optimus Black memory capacity is 2GB using eMMC and 512 MB of RAM, and connectivity has been HSDPA 7.2 Mbps or HSUPA 5.6 Mbps.
LG Optimus Black P970

-----------------------------------------------

LG Optimus Black specs:-


- Network Quad Band GSM & HSDPA
- Dimensions 122 x 64 x 9.2 mm
- Weight 109 grams
- Android OS 2.2 (Froyo) upgradable to Gingerbread
- Capacitive touchscreen TFT display 480 x 800 pixels, 4.0 inches
- Touch sensitive controls
- Optimus UI 2.0
- 5-megapixel rear camera, front 2-megapixel
- Features GPS (A-GPS), Wi-Fi 802.11 b / g / n, Wi-Fi Direct
- Connectivity 3.5 mm audio jack, Bluetooth v2.1 (A2DP)
- V2.0 microUSB port- MicroSD port up to 32GB,
- Li-Ion Battery 1500 mAh 
- Equipped with social networking integration, Digital compass, Google Search, Maps, Gmail, YouTube, Google Talk 


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Tuesday 24 May 2011

What is RAM (Random Access Memory)?....Types of RAMs?


Definition:- 
Random-access memory (RAM) is a form of temporary computer data storage.A type of computer memory that can be accessed randomly, that is, any byte of memory can be accessed without touching the preceding bytes.RAM is the most common type of memory found in computers and other devices, such as printers. It is a volatile memory storage, that is, data is lost when power is turned off.
RAMs
--------------------------------------------------------------

Some other uses of RAM:-
In addition to serving as temporary storage and working space for the operating system and its applications, RAM is used in numerous other ways.

1) Virtual memory
Most modern operating systems employ a method of extending RAM capacity, known as "virtual memory". A portion of the computer's hard drive is set aside for a paging file or a scratch partition, and the combination of physical RAM and the paging file form the system's total memory. (For example, if a computer has 2 GB of RAM and a 1 GB page file, the operating system has 3 GB total memory available to it.) When the system runs low on physical memory, it can "swap" portions of RAM to the paging file to make room for new data, as well as to read previously swapped information back into RAM. Excessive use of this mechanism results in thrashing and generally hampers overall system performance, mainly because hard drives are far slower than RAM.

2) RAM disk
Software can "partition" a portion of a computer's RAM, allowing it to act as a much faster hard drive that is called a RAM disk. A RAM disk loses the stored data when the computer is shut down, unless memory is arranged to have a standby battery source.

3) Shadow RAM
Sometimes, the contents of a relatively slow ROM chip are copied to read/write memory to allow for shorter access times. The ROM chip is then disabled while the initialized memory locations are switched in on the same block of addresses (often write-protected). This process, sometimes called shadowing, is fairly common in both computers and embedded systems.As a common example, the BIOS in typical personal computers often has an option called “use shadow BIOS” or similar. When enabled, functions relying on data from the BIOS’s ROM will instead use DRAM locations (most can also toggle shadowing of video card ROM or other ROM sections). Depending on the system, this may not result in increased performance, and may cause
incompatibilities. For example, some hardware may be inaccessible to the operating system if shadow RAM is used. On some systems the benefit may be hypothetical because the BIOS is not used after booting in favor of direct hardware access. Free memory is reduced by the size of the shadowed ROMs.

-------------------------------------------------------------------

Two most common types of RAM are:-


SRAM :- 
Static random access memory uses multiple transistors, typically four to six, for each memory cell but doesn't have a capacitor in each cell. It is used primarily for cache. It is made up of flip flops due to which no refresh cycle is needed, due to this SRAM is faster than DRAM. SRAM can give access times as low as 10 nanoseconds.Each bit in an SRAM is stored on four transistors that form two cross-coupled inverters. This storage cell has two stable states which are used to denote 0 and 1. Two additional access transistors serve to control the access to a storage cell during read and write operations. A typical SRAM uses six MOSFETs to store each memory bit.The most prominent use of SRAM is in the cache memory of processors where speed is very essential, and the low power consumption translates to less heat that needs to be dissipated. Even hard drives, optical drives, and other devices that needs cache memory or buffers use SRAM modules.


DRAM :-
Dynamic random access memory has memory cells with a paired transistor and capacitor requiring constant refreshing. As DRAM requires constant refreshing, therefore these RAMs are slower than SRAMs. DRAM supports access times of about 60 nanoseconds. It requires more power. The advantage of DRAM is its structural simplicity: only one transistor and a capacitor are required per bit.Because of its lower price, DRAM has become the mainstream in computer main memory despite being slower and more power hungry compared to SRAM.

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Other types of RAM are :-

FPM DRAM:-
Fast page mode dynamic random access memory was the original form of DRAM. It waits through the entire process of locating a bit of data by column and row and then reading the bit before it starts on the next bit. Maximum transfer rate to L2 cache is approximately 176 MBps.EDO DRAM: Extended data-out dynamic random access memory does not wait for all of the processing of the first bit before continuing to the next one. As soon as the address of the first bit is located, EDO DRAM begins looking for the next bit. It is about five percent faster than FPM. Maximum transfer rate to L2 cache is approximately 264 MBps.

SDRAM:-
Synchronous dynamic random access memory takes advantage of the burst mode concept to greatly improve performance. It does this by staying on the row containing the requested bit and moving rapidly through the columns, reading each bit as it goes. The idea is that most of the time the data needed by the CPU will be in sequence. SDRAM is about five percent faster than EDO RAM and is the most common form in desktops today. Maximum transfer rate to L2 cache is approximately 528 MBps.

DDR SDRAM:-
Double data rate synchronous dynamic RAM is just like SDRAM except that is has higher bandwidth, meaning greater speed. Maximum transfer rate to L2 cache is approximately 1,064 MBps (for DDR SDRAM 133 MHZ).

RDRAM:-
Rambus dynamic random access memory is a radical departure from the previous DRAM architecture. Designed by Rambus, RDRAM uses a Rambus in-line memory module (RIMM), which is similar in size and pin configuration to a standard DIMM. What makes RDRAM so different is its use of a special high-speed data bus called the Rambus channel. RDRAM memory chips work in parallel to achieve a data rate of 800 MHz, or 1,600 MBps. Since they operate at such high speeds, they generate much more heat than other types of chips. To help dissipate the excess heat Rambus chips are fitted with a heat spreader, which looks like a long thin wafer. Just like there are smaller versions of DIMMs, there are also SO-RIMMs, designed for notebook computers.

Credit Card Memory:-
Credit card memory is a proprietary self-contained DRAM memory module that plugs into a special slot for use in notebook computers.

PCMCIA Memory Card:-
Another self-contained DRAM module for notebooks, cards of this type are not proprietary and should work with any notebook computer whose system bus matches the memory card's configuration.

CMOS RAM:-
CMOS RAM is a term for the small amount of memory used by your computer and some other devices to remember things like hard disk settings,sytems clock settings,etc. This memory uses a small battery to provide it with the power it needs to maintain the memory contents.

VRAM:-
VideoRAM, also known as multiport dynamic random access memory (MPDRAM), is a type of RAM used specifically for video adapters or 3-D accelerators. The "multiport" part comes from the fact that VRAM normally has two independent access ports instead of one, allowing the CPU and graphics processor to access the RAM simultaneously. VRAM is located on the graphics card and comes in a variety of formats, many of which are proprietary. The amount of VRAM is a determining factor in the resolution and color depth of the display. VRAM is also used to hold graphics-specific information such as 3-D geometry data and texture maps. True multiport VRAM tends to be expensive, so today, many graphics cards use SGRAM (synchronous graphics RAM) instead. Performance is nearly the same, but SGRAM is cheaper.

Reasons To Why PCs Crash???


10 reasons why PCs crash.........
PC Crash



BSOD
Fatal error: the system has become unstable or is busy," it says. "Enter to return to Windows or press Control-Alt-Delete to restart your computer. If you do this you will lose any unsaved information in all open applications."


You have just been struck by the Blue Screen of Death. Anyone who uses MS Windows will be familiar with this. What can you do? More importantly, how can you prevent it happening?


1) Hardware conflict:-


The number one reason why Windows crashes is hardware conflict. Each hardware device communicates to other devices through an interrupt request channel (IRQ). These are supposed to be unique for each device.
For example, a printer usually connects internally on IRQ 7. The keyboard usually uses IRQ 1 and the floppy disk drive IRQ 6. Each device will try to hog a single IRQ for itself.
If there are a lot of devices, or if they are not installed properly, two of them may end up sharing the same IRQ number. When the user tries to use both devices at the same time, a crash can happen. The way to check if your computer has a hardware conflict is through the following route:


 Start-Settings-Control Panel-System-Device Manager.


Often if a device has a problem a yellow '!' appears next to its description in the Device Manager. Highlight Computer (in the Device Manager) and press Properties to see the IRQ numbers used by your computer. If the IRQ number appears twice, two devices may be using it.
Sometimes a device might share an IRQ with something described as 'IRQ holder for PCI steering'. This can be ignored. The best way to fix this problem is to remove the problem device and reinstall it.
Sometimes you may have to find more recent drivers on the internet to make the device function properly. A good resource is www.driverguide.com. If the device is a soundcard, or a modem, it can often be fixed by moving it to a different slot on the motherboard (be careful about opening your computer, as you may void the warranty).
When working inside a computer you should switch it off, unplug the mains lead and touch an unpainted metal surface to discharge any static electricity.
To be fair to Mcft, the problem with IRQ numbers is not of its making. It is a legacy problem going back to the first PC designs using the IBM 8086 chip. Initially there were only eight IRQs. Today there are 16 IRQs in a PC. It is easy to run out of them. There are plans to increase the number of IRQs in future designs.




2) Bad Ram:-


Ram (random-access memory) problems might bring on the blue screen of death with a message saying Fatal Exception Error. A fatal error indicates a serious hardware problem. Sometimes it may mean a part is damaged and will need replacing.
But a fatal error caused by Ram might be caused by a mismatch of chips. For example, mixing 70-nanosecond (70ns) Ram with 60ns Ram will usually force the computer to run all the Ram at the slower speed. This will often crash the machine if the Ram is overworked.
One way around this problem is to enter the BIOS settings and increase the wait state of the Ram. This can make it more stable. Another way to troubleshoot a suspected Ram problem is to rearrange the Ram chips on the motherboard, or take some of them out. Then try to repeat the circumstances that caused the crash. When handling Ram try not to touch the gold connections, as they can be easily damaged.
Parity error messages also refer to Ram. Modern Ram chips are either parity (ECC) or non parity (non-ECC). It is best not to mix the two types, as this can be a cause of trouble.
EMM386 error messages refer to memory problems but may not be connected to bad Ram. This may be due to free memory problems often linked to old Dos-based programmes.


3) BIOS settings:-


Every motherboard is supplied with a range of chipset settings that are decided in the factory. A common way to access these settings is to press the F2 or delete button during the first few seconds of a boot-up.
Once inside the BIOS, great care should be taken. It is a good idea to write down on a piece of paper all the settings that appear on the screen. That way, if you change something and the computer becomes more unstable, you will know what settings to revert to.
A common BIOS error concerns the CAS latency. This refers to the Ram. Older EDO (extended data out) Ram has a CAS latency of 3. Newer SDRam has a CAS latency of 2. Setting the wrong figure can cause the Ram to lock up and freeze the computer's display.
Mcft Windows is better at allocating IRQ numbers than any BIOS. If possible set the IRQ numbers to Auto in the BIOS. This will allow Windows to allocate the IRQ numbers (make sure the BIOS setting for Plug and Play OS is switched to 'yes' to allow Windows to do this.).


4 Hard disk drives:-


After a few weeks, the information on a hard disk drive starts to become piecemeal or fragmented. It is a good idea to defragment the hard disk every week or so, to prevent the disk from causing a screen freeze. Go to


Start-Programs-Accessories-System Tools-Disk Defragmenter


This will start the procedure. You will be unable to write data to the hard drive (to save it) while the disk is defragmenting, so it is a good idea to schedule the procedure for a period of inactivity using the Task Scheduler.
The Task Scheduler should be one of the small icons on the bottom right of the Windows opening page (the desktop).
Some lockups and screen freezes caused by hard disk problems can be solved by reducing the read-ahead optimisation. This can be adjusted by going to


Start-Settings-Control Panel-System Icon-Performance-File System-Hard Disk.


Hard disks will slow down and crash if they are too full. Do some housekeeping on your hard drive every few months and free some space on it. Open the Windows folder on the C drive and find the Temporary Internet Files folder. Deleting the contents (not the folder) can free a lot of space.
Empty the Recycle Bin every week to free more space. Hard disk drives should be scanned every week for errors or bad sectors. Go to


 Start-Programs-Accessories-System Tools-ScanDisk


Otherwise assign the Task Scheduler to perform this operation at night when the computer is not in use.


5 Fatal OE exceptions and VXD errors:-


Fatal OE exception errors and VXD errors are often caused by video card problems.
These can often be resolved easily by reducing the resolution of the video display. Go to


Start-Settings-Control Panel-Display-Settings


Here you should slide the screen area bar to the left. Take a look at the colour settings on the left of that window. For most desktops, high colour 16-bit depth is adequate.
If the screen freezes or you experience system lockups it might be due to the video card. Make sure it does not have a hardware conflict. Go to


 Start-Settings-Control Panel-System-Device Manager


Here, select the + beside Display Adapter. A line of text describing your video card should appear. Select it (make it blue) and press properties. Then select Resources and select each line in the window. Look for a message that says No Conflicts.
If you have video card hardware conflict, you will see it here. Be careful at this point and make a note of everything you do in case you make things worse.
The way to resolve a hardware conflict is to uncheck the Use Automatic Settings box and hit the Change Settings button. You are searching for a setting that will display a No Conflicts message.
Another useful way to resolve video problems is to go to


Start-Settings-Control Panel-System-Performance-Graphics


Here you should move the Hardware Acceleration slider to the left. As ever, the most common cause of problems relating to graphics cards is old or faulty drivers (a driver is a small piece of software used by a computer to communicate with a device).
Look up your video card's manufacturer on the internet and search for the most recent drivers for it.


6 Viruses:-


Often the first sign of a virus infection is instability. Some viruses erase the boot sector of a hard drive, making it impossible to start. This is why it is a good idea to create a Windows start-up disk. Go to


 Start-Settings-Control Panel-Add/Remove Programs


Here, look for the Start Up Disk tab. Virus protection requires constant vigilance.
A virus scanner requires a list of virus signatures in order to be able to identify viruses. These signatures are stored in a DAT file. DAT files should be updated weekly from the website of your antivirus software manufacturer.
An excellent antivirus programme is McAfee VirusScan by Network Associates ( www.nai.com). Another is Norton AntiVirus 2000, made by Symantec ( www.symantec.com).


7) Printers:-


The action of sending a document to print creates a bigger file, often called a postscript file.
Printers have only a small amount of memory, called a buffer. This can be easily overloaded. Printing a document also uses a considerable amount of CPU power. This will also slow down the computer's performance.
If the printer is trying to print unusual characters, these might not be recognised, and can crash the computer. Sometimes printers will not recover from a crash because of confusion in the buffer. A good way to clear the buffer is to unplug the printer for ten seconds. Booting up from a powerless state, also called a cold boot, will restore the printer's default settings and you may be able to carry on.


8) Software:-


A common cause of computer crash is faulty or badly-installed software. Often the problem can be cured by uninstalling the software and then reinstalling it. Use Norton Uninstall or Uninstall Shield to remove an application from your system properly. This will also remove references to the programme in the System Registry and leaves the way clear for a completely fresh copy.
The System Registry can be corrupted by old references to obsolete software that you thought was uninstalled. Use Reg Cleaner by Jouni Vuorio to clean up the System Registry and remove obsolete entries. It works on Windows 95, Windows 98, Windows 98 SE (Second Edition), Windows Millennium Edition (ME), NT4 and Windows 2000.
Read the instructions and use it carefully so you don't do permanent damage to the Registry. If the Registry is damaged you will have to reinstall your operating system. Reg Cleaner can be obtained from www.jv16.org
Often a Windows problem can be resolved by entering Safe Mode. This can be done during start-up. When you see the message "Starting Windows" press F4. This should take you into Safe Mode.
Safe Mode loads a minimum of drivers. It allows you to find and fix problems that prevent Windows from loading properly.
Sometimes installing Windows is difficult because of unsuitable BIOS settings. If you keep getting SUWIN error messages (Windows setup) during the Windows installation, then try entering the BIOS and disabling the CPU internal cache. Try to disable the Level 2 (L2) cache if that doesn't work.
Remember to restore all the BIOS settings back to their former settings following installation.


9) Overheating:-


Central processing units (CPUs) are usually equipped with fans to keep them cool. If the fan fails or if the CPU gets old it may start to overheat and generate a particular kind of error called a kernel error. This is a common problem in chips that have been overclocked to operate at higher speeds than they are supposed to.
One remedy is to get a bigger better fan and install it on top of the CPU. Specialist cooling fans/heatsinks are available from www.computernerd.com or www.coolit.com
CPU problems can often be fixed by disabling the CPU internal cache in the BIOS. This will make the machine run more slowly, but it should also be more stable.


10) Power supply problems:-


With all the new construction going on around the country the steady supply of electricity has become disrupted. A power surge or spike can crash a computer as easily as a power cut.
If this has become a nuisance for you then consider buying a uninterrupted power supply (UPS). This will give you a clean power supply when there is electricity, and it will give you a few minutes to perform a controlled shutdown in case of a power cut.
It is a good investment if your data are critical, because a power cut will cause any unsaved data to be lost.
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