What is a pen made out of?

Ball point pen body (outside protection):

-Metals

-Plastics

-Copper or Brass

- Sometimes aluminum

-Many other chemicals

Ball point pen insides (Inside pen):

-Tungsten carbide ball (The ball point)

-Plastic (the ink holder)

-Customized or selected colored ink

-Brass (Spring)

And that's your classic ballpoint pen, its more complicated than it looks :)