A computer virus is a type of malicious software program that can replicate itself and spread from one computer to another. It can corrupt data, software, operating systems, and slow down computer performance. There are many types of viruses including program viruses, boot viruses, macro viruses, and stealth viruses. It is important to use antivirus software, regularly scan devices, avoid opening suspicious emails or files, and keep software updated to help prevent virus infections.

1. COMPUTER VIRUS
JANGIDML@REDIFF.COM
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2. VIRUS
 VIRUS IS A SOFTWARE, CONTAINS SET OF
PROGRAMMES WHICH LEAD FORCED TO
WORK WITHOUT ANY COMMANDS &
INTERUPTION. THE COMPUTER VIRUS ARE
EXECUTABLE PROGRAMMES.
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3. EFFECTS : MAY BE ONE OR
MORE
 DATA : CORRUPT
 SOFTWARES : CORRUPT
 OPERATING SYSTEM : CORRUPT
 HARD DISK : CREATE BAD SECTORE OR
CORRUPT
 SLOW DOWN : PROGRAMMES
 PRINT : UN-USAL CHARACTERS
 HANG : PC OPERATIONS
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4. TYPES OF VIRUS
 PROGRAM VIRUS : .COM,.EXE,.DLL etc.
 BOOT VIRUS : INTERUPT BOOTING PROCESS
 MACRO VIRUS : EXECUTE SEQUENCE OF KEY
STROCKS
 STEALTH VIRUS : HIDE FROM ANTI-VIRUS
 POLY MORPHIC VIRUS : INFECT PROGRAMMES
 MULTIPARTITE VIRUS : BOOT & PROGRAMMES
 COMPANION VIRUS : INFECT PROGRAMMES WITH
.COM
 MALICIOUS PROGRAMS : INFECT PROGRAMS OF
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COMPUTER VIRUS

5. TIPS TO MINIMIZE VIRUS
RISKS
 AUTOMATIC PROTECTION BY ANTI-VIRUS
 SCAN : HARD DICK
 SCAN : FD,CD,USB DRIVE
 E-MAIL : SCAN & READ
 UPDATE : ANTI-VIRUS
 DOWNLOAD : CARE & SCAN
 AVOID COPIED SOFTWARES
 AVOID TO USE BORROWED CD,USB DRIVE
ETC
 USE BACKUP & RESCUE DISK
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6. POPULAR & DESTRUCTIVE
VIRUS
 Creeper,1971  Stuxnet ,2009
 Elk Cloner ,1982  Conficker Virus,2009
 The Morris  agent.btz ,2008
Worm,1988  Zeus ,2007
 ILOVEYOU,2004
 PoisonIvy ,2005
 Code Red,2001
 MyDoom ,2004
 Nimda,2001
 Fizzer ,2003
 Slammer,2003
 Backdoor.Bot
 Blaster
 Funlove
 Welchia
 Stration@mm
 Commwarrior-A,2005
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