It's not often you use a hammer when working on your car. Contrary to some beliefs, you cannot fix anything with a hammer and duct tape. A ball peen hammer, however, was developed specifically for working on your car. When fixing a damaged body panel, the specially shaped head on the ball peen hammer allows you to make measured, well aimed taps and blows to the car. It's a good tool to keep around since you do need a hammer from time to time, and the flat end of the head can be used to tap on anything you want.
It takes lots of experience to properly use a ball peen hammer on your car's body. If you want to learn, find some metal to practice on first, and work in small taps rather than trying to bang it out with one punch.
Check out a picture of a ball peen hammer.
* You can purchase this tool online through one of About.com's trusted online retailers.
