Avast is av software, just as Mcafee, Norton (nowadays Symantec) Trend and others. A common fault of users is that they think everything is a virus, but there are differences. You got viruses, trojans, spyware, adware, worms and some other things. People expect that a av software can handle them all. This is wrong thinking. Caused by a lack of knowledge (no offense) My advise: If you have a computer, take time to learn at least the basics. You have a car? You did learn how to handle it? Do the same with your system! Don’t immidiatly blame problems on the system or the software. Over 95% of the problems is caused by a lack of knowledge. I have tried to explain the differences HERE perhaps reading it clear some things up.