An airburst round, air burst grenade, or smart grenade is a type of tactical anti-personnel explosive ammunition, typically a shell or grenade, that detonates in midair, causing air burst effect fragment damage to an enemy. This makes it easier to hit enemy soldiers behind a wall, in a Defensive fighting position, or in a confined space or room. It is used on many guns, from artillery to the hand-held XM25 Individual Airburst Weapon System (derived from the XM29 OICW). Unlike traditional grenades, such as the 40 mm grenade, smart grenades can be electronically programmed to explode after traveling a certain distance. A fire control computer or some other electronic sighting system is used to quickly program the electronic fuse with any distance, as conditions dictate.