Despite what the article said about no programming required, ZZT was a very fun early programming environment. The creatures in the game were literally called O

Despite what the article said about no programming required, ZZT was a very fun early programming environment. The creatures in the game were literally called Objects and passed messages to each other to activate each other's functions to store information, move, sing, shoot, etc. By doing this in conjunction with the easy level builder, it was possible to manage fairly complex world and story state. Alan Kay may have approved, if he ever saw it.