These products typically scan every file that is opened or closed on your computer and detect viruses by matching the patterns in the file with the database of virus patterns. Any virus that is found is then neutralized or cleaned. Anti-virus products have advanced significantly in the last few years. They are now capable of recognizing mutating viruses which hide themselves by changing their signature patterns, and many of them even employ advanced heuristics to identify viruses whose patterns are not in the database. While these advances are useful and needed, they offer little protection against today s new threats.
Today s new threats arise from two distinct sources.
First, our computers are no longer isolated but are connected to millions of other systems via the Internet. Thus programs are no longer exchanged once in a while via diskettes but are downloaded regularly from Web sites. Today 11 million people download software off the Internet every month. Not surprisingly, there are far more viruses and far more infections than before. But viruses are only one facet of the PC security problem.