Piston Hammer - Ball Pen Hammer
Brass hammer for striking directly on metal parts. Ball Pein hammer for striking driving and seperating tools. Engineer's hammer for striking with heavy blows.
How to use a hammer:
Other than these three, their are many other types of hammers. Some others are Rubber mallets, piston hammers, framing hammer to name a few.
Hammers as seen in Basic Engine Building:
Here we used an engineers hammer to strike a metal rod going thru the engine block to bang out an oil gallery plug. Always eye protection while hammering anything.