The virus slows down the floppy disk drive and makes seven kilobytes of memory unavailable to DOS. Brain was written by Amjad Farooq Alvi and Basit Farooq Alvi, who at the time lived in Chah Miran, near Lahore Railway Station, in Lahore, Pakistan. The brothers told TIME magazine they had written it to protect their medical software from illegal copying, and it was supposed to target copyright infringement only.[2] The cryptic message "Welcome to the Dungeon", a safeguard and reference to an early programming forum on Dungeon BBS, appeared after a year because the brothers licensed a beta version of the code.