The number one goal of malicious hacking is industrial espionage, the WarRoom survey concluded, with theft of funds, passwords and data also reported. This is a program containing a concealed malicious code, and is often used to steal passwords. The login program of a computer is replaced with one that copies the passwords used by the computer owner. This information can then be used fraudulently. E-mail is a great way to communicate over the Internet, but is particularly suited for anonymity.
Many online scams depend on fraudulent e-mails.
The most familiar form of malicious code is the computer virus, a fragment of code that attaches to the boot sector of a disk or to executable files on the disk. Whenever the boot sector or host file is loaded into memory and executed, the virus is activated, spreading from computer to computer through floppy disks and computer networks. Some of these viruses reformat hard drives, destroying all their files. Others are simply nuisances, printing messages or graphics, playing music, or causing congestion that slows computers down. In 1988 a graduate student at Cornell University launched one of the most famous worm hacks.