what is the role of a virus scanner
Antivirus software Antivirus or anti-virus software (often abbreviated as AV), sometimes known as anti-malware software, is computer software used to prevent, detect and remove malicious software.[1]
Computer virus The Creeper virus was first detected on ARPANET, the forerunner of the Internet, in the early 1970s.[23] Creeper was an experimental self-replicating program written by Bob Thomas at BBN Technologies in 1971.[24] Creeper used the ARPANET to infect DEC PDP-10 computers running the TENEX operating system.[25] Creeper gained access via the ARPANET and copied itself to the remote system where the message, "I'm the creeper, catch me if you can!" was displayed. The Reaper program was created to delete Creeper.[26] In fiction, the 1973 Michael Crichton sci-fi movie Westworld made an early mention of the concept of a computer virus, being a central plot theme that causes androids to run amok.[27] Alan Oppenheimer's character summarizes the problem by stating that "...there's a clear pattern here which suggests an analogy to an infectious disease process, spreading from one...area to the next." To which the replies are stated: "Perhaps there are superficial similarities to disease" and, "I must confess I find it difficult to believe in a disease of machinery."[28]