Hammer

Hammer

A modern claw hammer
Types	Hand tool
Used with	Construction

A hammer is a tool or device that delivers a blow (a sudden impact) to an object. Most hammers are hand tools used to drive nails, fit parts, forge metal, and break apart objects. Hammers vary in shape, size, and structure, depending on their purposes.

Hammers are basic tools in many trades. The usual features are a head (most often made of steel) and a handle (also called a or ). Although most hammers are hand tools, powered versions exist; they are known as powered hammers. Types of power hammer include steam hammers and trip hammers, often for heavier uses, such as forging.

Some hammers have other names, such as sledgehammer, mallet and gavel. The term "hammer" also applies to devices that deliver blows, such as the hammer of a firearm or the hammer of a piano or the hammer ice scraper.

The use of simple hammers dates to about 2,600,000 BCE when various shaped stones were used to strike wood, bone, or other stones to break them apart and shape them. Stones attached to sticks with strips of leather or animal sinew were being used as hammers with handles by about 30,000 BCE during the middle of the Paleolithic Stone Age.

The hammer's archeological record shows that it may be the oldest tool for which definite evidence exists of its early existence.

A stone hammer found in Dover Township, Minnesota dated to 8000–3000 BCE, the North American Archaic period

Stone tapping hammer