A computer virus is a type of malicious software that replicates itself and spreads from one computer to another without the user’s knowledge or permission. These viruses are designed to infect and damage a computer system by altering or deleting important files, stealing sensitive information, and disrupting the normal functioning of the system.

One example of a computer virus is the Trojan horse. This type of virus disguises itself as a legitimate program or file, and when the user downloads and installs it, the Trojan horse reveals its true intentions and begins to wreak havoc on the system. This can include stealing personal information, such as passwords and financial information, and disabling important system functions.

Another example of a computer virus is the ransomware. This type of virus encrypts the user’s important files and demands payment in exchange for the decryption key. If the user does not pay the ransom within a specified time period, the files will be permanently deleted. This can be devastating for individuals and businesses, as important files such as documents, photos, and videos may be lost forever.

To protect against computer viruses, it is important to regularly update the operating system and antivirus software, avoid downloading and opening suspicious files or emails, and avoid visiting unknown or untrustworthy websites. Additionally, backing up important files on a regular basis can help to minimize the potential damage from a virus attack.

Overall, computer viruses are a serious threat to the security and stability of computer systems. By understanding the different types of viruses and taking the necessary precautions, individuals and businesses can help to protect themselves against these malicious programs.