Adware.popcap was on my computer?

I got a popup today that said something to the degree of my computer being infected, and a scan needed to be done by some anti-virus I’d never heard of. I started task manager and closed my browser. Then I booted my computer in safe mode because I hadn’t clicked on any ads or links, I clicked on a question answer on here. MalwareBytes found Adware.Popcap on my computer.

I’d like to know what it is and what it does, please help.

POPcan is a game site has great games but the adware is alittle bit anoying but usually harmless

but morethen likely it’s not that but something else thats triggering it