Dropped from aircraft and unmanned aerial vehicles, a glide bomb has wings or other aerodynamic surfaces that provide lift, so that its range is extended and its trajectory is not affected only by gravity, wind, and air resistance. Practical variants are electronically guided and may be precision-guided munitions.
Early glide bombs
There were several attempts, of varying success, to use gliding bombs late in the Second World War, but the available sensing and guidance technology were inadequate for effective use. Even television cameras, a reliable commodity today, could only transmit a crude picture from the nose of a bomb.
The U.S. AZON was a conventional bomb that had been equipped with aerodynamic control surfaces, and could be steered, by radio from a human operator, left and right in azimuth, hence the name. An improved version, RAZON, could be adjusted in range (i.e., range and azimuth). Guidance and control were totally manual, based on what the weapon operator could see in the television link, and using switches to adjust fins to shift the name — it was not "flown" with a control stick as is an aircraft.
One of the problems of the AZON and related weapons is that to be guided, they could not roll, as did conventional bombs. Rolling, however, stabilized the flight path, so the weapons operator both had to correct drift and aim at the target.
While the German Fritz-X is often called a guided bomb, most versions seem to have been rocket-assisted and really an air-to-surface missile. It had dramatic results, sinking the Italian battleship Roma after Italy surrendered and Germany kept fighting.
Modern glide bombs vary with the need for precision delivery, and the type of payload they carry.
The current GBU-39 Small Diameter Bomb and the GBU-53 Small Diameter Bomb in development are glide bombs, In foreign military sales, their lower weight also provides greater range for the same number of bombs, considered especially important by the Israelis. 
Weapons carrying cluster munitions are area-effect and do not need extreme precision, but they need guidance when attacking targets at long range. The Wind Corrected Munitions Dispenser is one such device.
Glide bombs have usually not been as precise as missiles or gravity bombs, but this is changing with the GBU-53. Another aspect of both Small Diameter Bombs is that they are small, such that many can be released at once from an aircraft at high altitude.
- Greg Goebel, [4.0 World War II Glide Bombs (2)]
- Israel’s Game Changer: GBU-39 Buster may prove highly lethal to Iran, September 15, 2008