Adventure for the Atari 2600, the First Action-Adventure Game

Warren Robinett began his career as an Atari videogame designer, where he designed Adventure for the Atari 2600, the first action-adventure videogame. The talk is about the implementation of Adventure. Because memory was extremely expensive in the late 70's, the program for Adventure had to fit into a 4K-byte ROM chip.  Therefore the program was very short. Nevertheless, the game had 30 rooms, and 18 objects of 12 different types -- the square Man (the player's avatar), the Chalice (the Grail-like goal of the game), 3 castles with matching keys to open them, 3 dragons and a sword to kill them, a bat that flew in and stole your stuff, a magnet that attracted things, several mazes and a bridge that let you cross its walls.  How was all this content jammed into 4K?  A good data structure was the heart of the game: the room-list and object-list.  There was also a very effective "Behavioristic" scheme for giving "desires" and "fears" to the creatures in the game—which caused them to flee from or pursue certain other objects. Within this highly-compressed game code can be seen the skeleton of the modern action-adventure game.