Heavy bombers are bomber aircraft capable of delivering the largest payload of air-to-ground weaponry and longest range of their era. Archetypal heavy bombers have therefore usually been among the largest and most powerful military aircraft at any point in time. In the second half of the 20th century, heavy bombers were largely superseded by strategic bombers, which were often even larger in size, had much longer ranges and were capable of delivering nuclear bombs.

A bomber is a military combat aircraft that utilizes air-to-ground weaponry to drop bombs, launch torpedoes, or deploy air-launched cruise missiles. Bombs were first dropped from an aircraft during the Italo-Turkish War, with the first major deployments coming in the First World War and Second World War by all major airforces, damaging cities, towns, and rural areas. The first bomber planes in history were the Italian Caproni Ca 30 and British Bristol T.B.8, both of 1913. Some bombers were decorated with nose art or victory markings.