On Demand Scanner - with Skinnable Simple Interface - just select what do you want to scan in which way and press the Play button.
On Access Scanner - resident scanning of all files being opened, read and written and behavior blocker monitoring dangerous actions of viruses.
E-mail scanner easily integrates with most mail clients and it checks both incoming and outgoing mails, it provides heuristic analysis of mail content to protect against new Worms.
Network Shield - scans traffic for malicious content - lightweight Firewall.
Resident protection for IM programs (e.g. MSN Messenger, ICQ) and P2P programs (e.g. Kazaa, DirectConnect).
Boot Time Scanner - scans disks in the same way and in the same time as Windows CHKDSK does (on NT/2000/XP only).
Explorer Scanner - right click on the object allows you to scan it.
Screen Saver Scanner - scans PC during your coffee breaks.
Virus Chest - safety isolated folder to store infected, suspicious and even some system files - to restore them.
True incremental updates of size under 100 KB are available at least twice a week and within couple of hours in the case of emergency of new virus. avast! automatically checks for new updates - downloads, installs and loads them without restart or logoff. Program upgrades are available time to time, they are incremental too (about 300 KB).
avast! Free Antivirus is available in English, French, German, Italian, Japaneese, Polish, Portuguese, Russian, Spanish and other languages - check http://www.avast.com/eng/down_home.html to download avast! in your language.