A hammer is a tool that delivers an impact to an object. The most common uses for hammers are to drive nails, fit parts, forge metal, and break apart objects. Hammers often serve a specific purpose, and vary in shape and structure. The term "hammer" also applies to some devices that deliver blows, e.g., the caplock mechanism of firearms.

The hammer is a basic tool of many professions. The usual features are a handle and a head, with most of the weight in the head. The basic design is hand-operated, but there are also many mechanically operated models, such as steam hammers, for heavier uses.

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Guides that use

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