Cluster bombs are controversial weapons consisting of a canister which breaks apart to release a large number of small bombs. Click on the links in the image to find out more.
A range of so-called bomblets can be employed to attack different targets such as armoured vehicles or people - or to start fires.
They can cover a large area but do not have precision guidance. Dropped from medium to high altitudes, they can wander off target.
There is a significant "dud rate" of about 5%. In other words, many do not explode but, rather like landmines, litter the ground with the potential to explode years later.
One widely-used cluster bomb is the US-manufactured CBU-87/B "combined effects munition". Weighing 950 lbs (430 kgs), it is the carrier for 202 BLU-97/B bomblets.
It can be dropped from a wide range of strike aircraft.
Wind corrected munitions dispensers - a tail kit containing guidance equipment - can be used to improve accuracy. Dropped from 40,000 ft, it can steer to a target area about nine miles away.