A hammer's a tool meant to deliver an impact to an object. The most common uses are for driving nails, fitting parts, forging metal and breaking up objects. Hammers are often designed for a specific purpose, and vary widely in their shape and structure. Usual features are a handle and a head, with most of the weight in the head. The basic design's hand-operated, but there're also many mechanically operated models for heavier uses. The hammer's a basic tool of many professions, and can also be u… (More on Hammer)