Avast! Antivirus is an anti-virus program developed by ALWIL Software based in Prague, Czech Republic, first released in 1988. Avast! was one of the first on-access antivirus programs to be released for Windows x64 edition. Avast! 4 Home is a popular full-featured freeware anti-virus applications for Microsoft Windows users. As of July, 2008 it has had over 25 million downloads on Download.com. As of March 7, 2008 Avast! (Home version) has had 50 million registered users.
Avast! is aimed at preventing several types of computer threats, including those that are not technically computer viruses such as spyware and even rogue anti-spyware, and can also make a virus Recovery DataBase which is used to recover files when they are infected (instead of deleting them). The program is available with text and voice translations for 27 languages.