Click here for free Lucky for Life tickets. The servers were back on line by 4 p.m. The program didn't damage any machines, or destroy any important data. The program is technically a worm, which uses e-mail and networks to spread to other computers.
Viruses are programs that attach themselves to other files and reproduce inside computers.
When users clicked on the attachment, they got a joke text about relationships. Behind the scenes, the program used Microsoft Outlook's address book to send copies of itself to other computers. It also spread through users of internet chat rooms. Information from The Associated Press was used in this report.