Virus-like program that spreads automatically to other computers by sending itself out by email or by any other means. A program that propagates itself by attacking other machines and copying itself to the affected machine.
Worms have self-replicating code that travels from machine to machine by various means. A worms first objective is merely propagation. Worms can be destructive depending on what payload they have been given. Worms may replace files, but do not insert themselves into files.
Comment:
Small.DAM is a downloader trojan that comes into the user's computer as an attachment from spam mails. It uses rootkit components to hide its presence from the user. It spreads through spam mails