Computer viruses are malicious software that replicate by altering other programs, leading to various issues like slower performance and unexpected behavior. Types of viruses include boot viruses, program viruses, and macro viruses, while malware encompasses various harmful software like spyware and adware. Prevention measures include installing antivirus software, keeping systems updated, and practicing safe browsing habits.

1. COMPUTER VIRUS & MALWARE
A thug for computer

2. WHAT IS A COMPUTER VIRUS??
• A type of malicious software program ("malware")
• Replicates itself by modifying other computer programs
• Written to alter the way a computer operates
• Designed to spread from one computer to another.
• Destructive programs that delete or corrupt files
• Interfere with computer operations
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3. SYMPTOMS OF COMPUTER VIRUSES
• Slower Internet and Processing. ...
• Unexpected Computer Behavior. ...
• Sudden Freezes & Crashes. ...
• Error Messages. ...
• Advertisements. ...
• Outgoing Emails. ...
• Missing or Extra Files. ...
• Hardware and Accessory Problems.
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4. TYPES OF MAJOR COMPUTER VIRUSES
•Boot Virus
•Program Virus
•Micro Virus
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5. BOOT VIRUS
• A type of virus that infects the boot sector of floppy disks
• Also infects the MasterBoot Record (MBR) of hard disks
• Hides in the boot code for a media device, such as a disk
• Runs automatically when the media is loaded
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6. PROGRAM VIRUS
• They are often called Trojan Horse Virus
• They hide in an apparently useful program
• Then run when the program is opened.
• Can travel on media like a CD by by email attachment.
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7. MACRO VIRUS
• Computer virus that "infects" a Microsoft Word or similar application
• Causes a sequence of actions to be performed automatically when the
application is started
• Macro viruses tend to be surprising but relatively harmless.
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8. SOME MINOR COMPUTER VIRUSES
•File infector viruses
•Multipartite viruses
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9. FILE INFECTOR VIRUSES
• File infector viruses infect program files
• normally infect executable code, such as .com and .exe files.
• infect other files when an infected program is run
• Many of these viruses are memory resident.
• Examples :Jerusalem and Cascade.
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10. MULTIPARTITE VIRUSES
• Multipartite (also known as polypartite) viruses
• Infect both boot records and program files
• These are particularly difficult to repair.
• The same holds true for cleaning infected files.
• Examples :One_Half, Emperor, Anthrax and Tequilla.
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12. How Do Computer Viruses Spread?
Computer viruses usually spread in one of three
ways:-
•From Removable media.
•From Downloads off the Internet.
•From e-mail attachments.

13. MALWARE

14. What is malware?
•Malware is a malicious software that
gets installed in your device and performs
unwanted tasks.
• Mainly designed to transmit information
about your web browsing habits to the
third party

15. TYPES OF MALWARE
Viruses
Trojan Horse
Spyware
Spam
Adware
Rootkits
Scareware
Worms

16. Viruses
• Software that replicates itself and spreads by damaging
and deleting the files.
• Virus enters your device via attached images, greeting,
audio/video files , downloads etc.

17. Spyware
• Spyware is a program that gets installed without the user’s
permission.
• It monitors the user’s activities on the internet and transmits
that information to the third party.

18. 
Adware
• Software where advertising banners are displayed while any
program is running.
• It automatically downloads to your device while browsing any
website
• It is used by companies for marketing purposes

19. Scareware
Software that is designed to trick the user into buying
or downloading unwanted software.

20. Worms
• Malicious program that make copies of itself on local device,
network shares etc.
• They make the working of your device slower.

21.  Trojan Horse
• A Trojan Horse is a program containing malicious or
harmful code.
• Entering a computer, it performs various tasks like
corrupting files and sending out personal information.

22. 
Spam
• Method of flooding the internet with the copies of the same message
• It is for the purpose of advertising, phishing, spreading malware etc.

23. Rootkits
• Software hidden deep inside your device which remains
undetected.
• It transmits all your sensitive information

24. PREVENTIONS AGAINST VIRUSES
• Install Anti-Virus/Malware Software.
• Keep Your Anti-Virus Software Up to Date
• Keep Your Operating System Current.
• Secure Your Network.
• Think Before You Click.
• Keep Your Personal Information Safe.
• Don’t Use Open Wi-Fi.
• Back Up Your Files
• Use Multiple Strong Passwords
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25. ANTI-VIRUS
• Computer software used to prevent, detect and remove malicious
software
• Provides signature-based detection of malware
• May also prevent spyware and adware, along with malicious
programs
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26. BASIC FUNCTIONS OF ANTI-VIRUS
• Scanning directories or specific files for known malicious patterns
• Allowing users to schedule scans so they run automatically
• Allowing users to initiate new scans at any time; and
• Removing any malicious software it detects.
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27. DIFFERENCE BETWEEN PAID AND FREE ANTI-VIRUS
•Free antivirus software generally only searches your
computer using signature-based detection .
•Paid antivirus software will usually also include
heuristics to catch new, or zero-day threats.
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28. SOME ANTI-VIRUSES
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29. CONCLUSION
• In the context of the world the computer viruses are the bad who
distract the life of the normal people.
• And to stop them anti-viruses are created
• Anti-viruses are the police in our nation who protect us
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30. THANK YOU
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