A worm is an infected program code that usually spreads through the existing infrastructure, network connections or emailattachments and causes damage on other systems. Worms can also use the user 's address book to spread.
Worms are malicious, autonomous program routines. They are malicious codes that, once coded and released, automatically multiply to infect as many computers as possible. They penetrate the systems via security holes and cause damage by triggering unwanted actions. These can be messages that suddenly appear on the screen, but they can also deletefiles, formathard disks, or load the processor with pointless tasks.