Antivirus software are programs that help protect your computer against most viruses, worms, Trojan horses, and other unwanted invaders that can make your computer "sick."
To help keep your computer healthy, you must install an Antivirus (Anti-malware) program. There are many. Most programs include antispyware and anti-phishing. Do a Google search to find put which one is right for you. You must also ensure both the program and the virus signature files are up to date. These updates are generally available through your subscription and can be set to perform automatically.