avast! is a brand of antivirus software. It is a free downloadable software that is compatible with Windows 8 through Windows XP. It has many features, Avast! Cloud services and upgrades can be bought from inside the program. There are no PC maintenance features. The latest version, 8.0.1488 was released 2 May 2013. In May 2013, it was the top download of free antivirus of Softonic.