A jackhammer is a pneumatic tool that combines a hammer directly with a chisel. It was invented by Charles Brady King. Hand-held jackhammers are typically powered by compressed air, but some use electric motors. Larger jackhammers, such as rig mounted hammers used on construction machinery, are usually hydraulically powered. They are usually used to break up rock, pavement, and concrete. In modern terminology, a "jackhammer" does not have the capacity to drill rock.

A jackhammer operates by driving an internal hammer up and down. The hammer is first driven down to strike the back of the bit and then back up to return the hammer to the original position to repeat the cycle. The bit usually recovers from the stroke by means of a spring. The effectiveness of the jackhammer is dependent on how much force is applied to the tool.

Read more about Jackhammer:  History, Terminology, Use, Bits (Chisels), Health