A rocket is a self-propelled, unguided weapon system powered by a rocket motor. Rockets are used primarily as medium and long-range artillery systems, although historically they have also seen considerable use as air-to-ground, some use as air-to-air weapons, and even a few examples of surface-to-air devices. Examples of modern surface-to-surface rocket systems include the BM-27 Uragan and M270 Multiple Launch Rocket System.

In military parlance, a rocket differs from a missile primarily by lacking an active guidance system; early missiles were known as "guided rockets" or "guided missiles". Some rockets were developed as unguided systems and later upgraded to guided versions, like the GMLRS, and these generally retain the term "rocket" instead of becoming missiles. Rockets or missiles that travel underwater, like the VA-111 Shkval, are known as torpedoes no matter what their propulsion system is.

Early development

The use of rockets as some form of artillery dates back to medieval China where devices such as fire arrows were used (albeit mostly as a psychological weapon), and gradually spread to Europe and the Middle East. Rockets became a significant weapon during the 20th Century, when precise manufacturing processes made relatively accurate rockets possible.