Horse artillery was a type of light, fast-moving an fast-firing artillery which provided highly-mobile fire support to European and American armies (especially to cavalry units) from the 17th to the early 20th century. A precursor of modern self-propelled artillery, it consisted of light cannons or howitzers attached to light but sturdy two-wheeled carriages called caissons or limbers, with the individual crewmen riding either the horses or the caissons into battle. This was in contrast to the field or "foot" artillery, where the artillery pieces were heavier but of larger caliber and the crew marched on foot.