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Mirror is nothing utility in antivirus software

Application software

These programs are called "Antivirus Software". You can find these all over the place, I wouldn't recommend downloading a free one you found on the internet as those are somewhat likely to contain a virus. I personally use Norton Antivirus to protect my computer, I haven't had a virus in quite some time. Here is a list of Antivirus Software that I know is safe that you can use for your PC.

Norton Antivirus

McAfee

Avast

Vipre Antivirus

Kaspersky

Antivirus software will notice about the virus,malware,spyware etc