What is Antivirus program?

Alternatively referred to as an antivirus software, AVS, antivir, or just AV. An antivirus program is a software utility designed to protect your computer or network against computer viruses. If and when a virus is detected, the computer displays a warning asking what action should be done, often giving the options to remove, ignore, or move the file to the vault.
If a virus infected a computer without an antivirus program, it may delete files, prevent access to files, send spam, spy on you, or perform other malicious actions.