Vroom! Blast the alien spaceships before they demolish you.
You strive for points and to make progress in the territory of the space world. Given that this was a very early game, the graphics permitted for pretty much the surroundings just changing color. Half Life, it's not. But the little game was challenging and with its devilish simplicity, had you hooked before long. You felt really proud if you could survive long enough to beat more and more levels.
This game did not make the shift into the modern era, but it was a lot of fun and remains one of the better memories for me from the salad days of gaming.