New viruses pop up more and more frequently all the time. Also their spreading could be much faster than it used to be several years ago. The main problem is not to add their detection into the antivirus product but the fact that most of the users do not use any antivirus program at all or they still have some ancient version which they have got together with their computer for free.

ALWIL Software, the producer of avast! has decided that since June 1, 2001 avast! will be free of charge for home users which do not use their computer for profit.  The only thing you have to do is to register online. The whole process is very simple: you have to download the program from our web page. Then you need to install it - you'll install the trial version which is fully functional for the period of sixty days. During this period, you can register yourself on avast! 4 Home Free Registration and you will receive your license key by E-mail in about 30 minutes. Insert this key into the avast! 4 Home and you will receive the non-restricted version of avast! 4 Home Edition including the access to the update service (incremental update of virus database) for one year. After this period you can reregister to obtain the new free license key.

avast! 4 Professional Edition is a collection of high-end technologies that work in perfect synergy, having one common goal: to give you the top grade protection against computer viruses. It represents an ideal solution for any Windows-based workstation.

http://www.avast.com/eng/avast_4_professional.html