The first full-stealth computer virus. In 1986, Brain was developed by Pakistani brothers Basit and Amjad Farooq Alvi, who were annoyed at having their heart monitoring software copied for free. Aimed at the IBM PC, the Brain virus only slowed down the floppy disk drive and did no other damage. By replacing the boot sector in the floppy disk, a message would display claiming infection and asking for payment to innoculate the machine. See
virus and
stealth virus.