system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How does antivirus software get created?

With so many viruses and malware out there that can do a variety of harmful effects to your computer (up to corrupting your OS), how do antivirus companies like McAffee and Symantec track and effectively create software to combat these viruses?
gpt
> antivirus companies like **McAffee and Symantec** track and effectively create software to combat

They don't.

More seriously though... AV vendors use a handful of tricks to try to detect and combat malicious software. nothing is perfect, though, they just do their best. Some common techniques:

1. blacklists - this is the most rudimentary thing you can do and is the backbone of essentially all modern anti virus software. If you know that a piece of software is bad, you save a signature of it so that the next time you see it you know it's bad and can stop it. the companies have teams dedicated to analyzing software and creating signatures and constantly update their databases.

2. heuristics - this is more sophisticated, you have your software inspect and examine a piece of unknown software in order to automatically analyze what it does, and you make an educated guess based on it. AV usually have options to dial the heuristics up or down since more stringent heuristics detection means more hits means better protection means more false positives.

3. sometimes an AV will just let an unknown software actually run in an isolated sandbox then watch what it does to see if it does anything bad.

4. if you *really* want to be secure, you can use a whitelist system, where you only allow anything in your database. anything unknown gets blocked. this would be a huge PITA to use and is exceedingly rare, and it's not really traditionally part of an AV either.