Avast!

Avast! Antivirus is an antivirus program developed by AVAST Software a.s. (former ALWIL Software a.s.), a company based in Prague, Czech Republic. It was first released in 1988. Avast! is based on a central scanning engine that is certified by ICSA Labs and West Coast Lab's Checkmark process and incorporates anti-spyware technology, also certified by West Coast Lab's Checkmark process, as well as anti-rootkit and self-protection capabilities. It is a multiple recipient of the Virus Bulletin VB100 Award, for detection of 100% of "in-the-wild" viruses, and is a past winner of the Secure Computing Readers' Trust Award. The name Avast comes from "Anti-Virus-Advanced-Set".
Avast! Free Antivirus is the freeware version of Avast! antivirus software available to Microsoft Windows and Linux users, while Avast! Pro Antivirus is offered to businesses and users that want additional features. Priority updates are delivered automatically using PUSH update technology in Avast! Pro Antivirus. Avast! Pro Antivirus also has a command line scanner and a script blocker.
Avast! Antivirus is a widely used antivirus program, with 130 million users worldwide as of September 2010

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