See all articles from CATS v6 n12
In May 1984 issue of Scientific American, A. K. Dewdney in his Computer Recreations column describes a game called Core War. The game is run by a monitor program called MARS (Memory Array Redcode Simulator). Essentially what the program does is to control two other programs written in an assembly-like language called REDCODE. The two programs are designed to try to destroy each other. They do this by somehow stopping the other program from running. They can put bad data in the middle of the program, take over control of the program, etc.