[efoote868]

The idea behind a patent is this: I teach the world how to do something, and for a bit of money, the government grants me a monopoly on my idea for a length of time. It gives me an offensive weapon to pursue those that don't pay me for my invention. This includes derivatives of my invention (e.g., I invent the bicycle, someone else invents a banana seat for the bicycle. My patent still covers their invention, so they can't produce bicycles with banana seats without paying me.) It does not give me a right to produce my invention (I'd still have to pay the person that invented the wheel). It is considered very strong protection.

A copyright is a weaker form of protection. It gives me a right to what I write or record and distribute it. It protects the form of expression, not the subject. For instance, I could re-write Harry Potter from Hedwig's perspective, and in telling the story differently gain rights to this new work and sell it as my own. J.K. Rowling couldn't do anything about it.