Your antivirus program is like a kind of like a tough bouncer you hire to guard your computer. But your bouncer needs information in order to do her job! She needs a list of bad guys (viruses) so she knows who to throw out. If your bouncer’s list of bad guys (virus definition list) is one month old, last week’s newest bad guy is going to waltz right by her.

Don’t forget to update, so your bouncer can do the job you hired her for!