How it began
Brain was written by the brothers Basit Farooq Alvi and Amjad Farooq Alvi in Lahore, Pakistan, and released in its first form on January 19, 1986. Basit was 19 at the time. The brothers told Time magazine they wrote it to protect their medical software from illegal copying. It is considered the first computer virus for the IBM Personal Computer and compatibles.
How it works
Brain replaced the boot sector of a floppy disk with a copy of itself, moved the real boot sector elsewhere on the disk and marked those sectors as bad. Infected disks usually showed five kilobytes of bad sectors and a label changed to "(c)Brain". The virus slowed the floppy drive and took seven kilobytes of memory from DOS. It checked the drive number and deliberately avoided hard disks, and it was not destructive.
How it spread
The virus traveled on floppy disks and reached the United Kingdom, the United States and other countries. Its code carried the brothers' address and three phone numbers with a message telling users to contact them for "vaccination". Their phone lines were overloaded with calls from people demanding that their machines be disinfected.
What changed first
Brain caused the first virus epidemic among IBM PC compatible computers and became known as the Pakistani flu. The brothers were stunned by the reaction and tried to explain to callers that their motive had not been malicious. The virus was also known by the names Lahore, Pakistani and Pakistani Brain.
Where it stands today
The brothers stayed in business in Lahore, running an internet service provider called Brain NET with a third brother, Shahid. In 2011, 25 years after the release, the security researcher Mikko Hypponen traveled to Lahore and filmed a documentary interview with them.
