What is a Virus?
A virus is a piece of malicious program code designed to disrupt or damage computer systems by adding itself (or a variant of itself) to commonly used system or program files. Viruses are self replicating, spreading from one ‘infected’ system to another. There are over 70,000 computer viruses in existence, with around 400-500 new viruses being discovered every month.
What is Antivirus Software
Antivirus or AV software is simply software you install onto your computer which detects and removes viruses and also monitors computer activity to prevent the introduction of viruses onto your computer e.g. by introducing an infected USB stick, downloading compromised files from the internet or opening a malicious webpage.
Antivirus software also protects you from many other types of malicious computer programmes or ‘malware’ such as browser hijackers, ransomware, keyloggers, backdoors, rootkits, trojan horses, worms, adware and spyware to name a few.
One of the key things to bear in mind is that computer viruses much like biological viruses are constantly evolving and changing. For your antivirus software to be able to protect against the latest viruses you must keep your ‘virus definitions’ up to date. Virus definitions are a list of the profiles of known viruses. Your computer software uses the definitions to compares files on your computer to the ones in its list of known viruses and takes action such as putting files in quarantine or deleting files when it spots a match.
To ensure your definitions are up to date ensure automatic or regular updates are turned on in the software settings.