Computer viruses and electronic mail

Today the Internet is a valuable source of information as well as a powerful communication medium, with undoubted social and economic bene-fits, however it also poses some security risks. Viruses may hide in email at-tachments or in apparently innocent applications directly downloadable from the Internet. In this work we give a brief overview of virus types and main de-fense techniques. Then we present statistical data of virus attacks revealed by an anti-virus SW activated on our e-mail server, and discuss results in terms of virus types and temporal distribution.