The GBU-39/B Small Diameter Bomb (SDB) is a 250-pound (110 kg) precision-guided glide bomb that is intended to provide aircraft with the ability to carry a higher number of more accurate bombs. Most US Air Force aircraft will be able to carry a pack of four SDBs in place of a single 2,000-pound (910 kg) bomb. It first entered service in 2006. The Ground Launched Small Diameter Bomb (GLSDB) was later developed to enable the SDB to be launched from a variety of ground launchers and configurations.

A precision-guided munition (PGM), also called a smart weapon, smart munition, or smart bomb, is a guided munition intended to hit a specific target, to minimize collateral damage and increase lethality against intended targets. During the Persian Gulf War guided munitions accounted for only 9% of weapons fired, but accounted for 75% of all successful hits. Despite guided weapons generally being used on more difficult targets, they were still 35 times more likely to destroy their targets per weapon dropped.