Jason Jupiter, Star Cadet is a platform game for the MS-DOS PC written by Neil A. Drage and published on a cover disk of the magazine PC Plus in 1989.
The video game uses colour text mode graphics. Drage has stated that it was inspired by the Sinclair Spectrum games Manic Miner and Jet Set Willy. In spite of its simplicity, the game has enjoyed lasting popularity and has been recently remade as an online Java applet with enhanced sound effects.
It was followed by a sequel, Jason Jupiter II.
Source: Wikipedia, "Jason Jupiter", available under the CC-BY-SA License.