What worries computer experts the most is the fact that MyDoom is an example of a new breed of professionally created worms that are more difficult to
detect and move faster. These better-built worms also are used by criminals to turn a profit.
Experts say the creation of MyDoom was almost certainly funded by e-mail spammers. The worm takes possession of a computer -- either at a home or one
used in business -- and turns the machine into a remotely controlled robot programmed to send spam e-mail messages.
With hundreds of thousands of these zombie computers sending spam, the chances of shutting down the flow are almost zero.
While the inner workings of the worm aren't a strong departure from earlier ones, the fact that it was professionally created with a criminal profit
motive is a big shift. Instead of sloppily made worms from amateurs, professional software writers -- motivated by money -- can create worms that will
spread faster and work more efficiently, said Roger Thompson, director of malicious-code research for TruSecure, a Herndon, Va.-based anti-virus firm.