Super Hi-Res Chess

Super Hi-Res Chess was a novelty computer program for the Apple II written by (then) Apple Computer applications programmer Bruce Tognazzini in 1978, early in the history of Apple computer. It was a practical joke program purporting to be a chess game in high-resolution (hi-res) graphics, but which actually contained no chess or graphics. When the unsuspecting user tried to run the program, it promptly crashed with a syntax error, appearing to return the user to the Applesoft BASIC command line input mode. However, when the user attempted to use any BASIC or Apple DOS commands, there would be humorous results, since the program was actually still running and only pretending to be the Apple's command line processor. Many different commands were "parodied", with silly error messages resulting.

"Tog" later expanded the program to include both the LISP and UCSD Pascal language syntax, redistributing it under the name "Cattlecar Galactica."

The program's name appeared in the directory of the floppy disk, but opening and listing this file revealed no useful contents. Instead, the user found only hundreds of page-feed commands and a small amount of seemingly random code. That's because that's all there was. The actual program on the disk was hidden in plain sight. It was called "Applesoft," for Applesoft BASIC, the name of Microsoft's floating point BASIC licensed by Apple in the early years. Because programmers expected to see a copy of Applesoft on every disk, they would never even suspect they should look there for the program. Naive users, on the other hand, were just as likely to look there as anywhere else, giving them the upper hand in discovering the actual program.

The way out of the program—the goal of the game—was equally stacked against programmers. The magic word for escaping the program and gaining access to the code was "egress," with sufficient clues that English majors could easily escape, but programmers unfamiliar with the word could not. (English majors often found their way out within about 30 minutes; some programmers took a week or more, working their way through the disk by track and sector, looking for clues in the underlying code.)

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