Zaxxon was originally available on the Commodore 64, Atari 2600 and Apple II (among others) in the style of an arcade shooter game. You are the commander of a airship and have to fight your way through each level, taking on enemies with your ammunition and dodging obstacles that get in your way - all while trying to keep an eye on your fuel so that it doesn't run out! Quite an addictive game. Runs best on new PCs using DOSBox (See Essential Utilities link on menu) if you don't have access to a very old, slow one.