Antivirus programs are an effective way to protect computers from viruses by identifying and removing viruses from memory, storage, and incoming files. Many computers come pre-installed with antivirus software. Antivirus programs work by scanning for malicious programs and files downloaded from the web, email attachments, and removable media. They use virus signatures to identify known virus codes and regularly update these signatures to protect against new viruses. While no method can guarantee complete safety, installing and regularly updating antivirus software helps safeguard computers and networks from loss or damage from computer viruses.