Carpenter's Hammer - Claw Hammers are the most common type of hammer and probably the one that comes to mind when most people think about a hammer. They are very versatile and can be used for a great many jobs so are an absolute must for any tool bag. The claw is used as a lever; it generally has a notch which is used to lever out nails from timber. The claw is inserted under the head of the nail so that it catches - this can take a little jiggling about. The nail is then levered out by pulling back on the handle and using the curve of the claw as the fulcrum. The claw can be used to lever other things, such as floorboards, but excessive use can put strain on the join between the head and handle, so check this regularly.