There is no known individual who invented the hammer because hammers have been used for centuries. There are records from Ancient Rome and the Middle Ages that discuss hammers and their usage.
The term "hammer" includes a wide variety of tools that are used for striking objects. The most well-known type of hammer is a carpenter's hammer, which has a claw on one end. This type of hammer likely developed during Roman times.
Other types of hammers include blacksmith's hammers, machinist's ball peen hammers, stone hammers, bricklayer's hammers and tack hammers. Each of these types varies in size and weight, depending on its purpose. A pounder, or hammerstone, was likely the first hammer to have a handle.