Fire support is long-range firepower provided to a front-line military unit. Typically, fire support is provided by artillery or close air support (usually directed by a forward observer), and is used to shape the battlefield or, more optimistically, define the battle. Battleships, for example, have also been a viable form of fire support in the past, being the main effort in naval warfare. Fire support's history and lineage traces through the advent of cannons in warfare as artillery, a major shaping force on the battlefield since its inception. Fire support, as an extension, is the marriage of artillery to the forces in contact. It is the direct ability to properly utilize artillery. As opposed to direct fire, that of the forces in contact, fire support utilizes artillery and close air support.
In the US Army, line companies in standard Heavy Brigade Combat Teams often utilize Fire Support Teams, or FST mounted in forward support vehicles to observe and adjust fires.