Wikipedia: Moon Patrol

Moon Patrol is a classic arcade game by Irem that was first released in 1982. It was licensed to Williams for U.S. distribution.The player controls a moon buggy, viewing it from the side, that travels over the moon's surface. While driving it, obstacles such as craters and mines must be avoided. The buggy is also attacked by UFOs from above and tanks on the ground. Moon Patrol was one of the earliest linear side-scrolling shoot'em ups and the first game to feature parallax scrolling.