There are many different types of viruses and worms one in particular being the Netsky. This is actually a prolific family of computer worms. This family of worms is perhaps most famous of all for comments contained within the code of its variants insulting the authors of the Bagle and MyDoom worm families. In both these cases, the worm was sent out as an email and worked by enticing recipients to open an attachment. Once a recipient had opened this attachment the attached program would scan the computer for email addresses and email itself to all the addresses found.