January 19, 1986 - The First Computer Virus for MS DOS is Released

The first virus for MS DOS was made by two brothers: Basit and Amjad Farooq Alvi. Nicknamed “Brain”, the virus worked by replacing the Boot Sector of a floppy disk (the section that contains machine code to be loaded into RAM) with a copy of itself. Upon running this floppy disk, users would see text stating where the two brothers live, their phone number, and the statement that they would fix any infected floppies that were reported. As you might expect, the brothers did not expect the virus to have so many victims.