Most missiles are guided weapons, usually rocket powered, that are designed to carry a payload to a target and destroy it. Missiles are defined by their target type and mode of delivery.
Air-to-air missiles are used by aircraft to shoot down opposing aircraft. Air-to-surface missiles are fired from aircraft at ground targets. Conversely, surface-to-air missiles are launched from the ground at aircraft and airborne targets. Anti-radiation missiles are designed to destroy radar sites.
Cruise missiles attack their target using an aircraft-like course. They fly at a specific speed and altitude (hence the name, cruise). Most possess sophisticated terrain-following radar that allows them to fly very close to the ground at high speeds. Cruise missiles can be air-launched, ground-launched, or ship/submarine-launched.
Ballistic missiles fly at ultra high speed and follow a ballistic arc to get to the target.