joe is correct. The hammer is one of the most useful tools in your box. In the wrong hands, however, it can definitely cause the most problems. I do take a little issue with the comment about using a smaller hammer. Sometimes this is correct, and sometimes not. You need at least four hammer sizes in your box. You know, the right tool for the right job.
When I worked in a shop many years ago, I was known for my prowess with a hammer. I like to think that they were impressed with the use of the other tools in my box as well.
Have a great day,