A utility patent is what most people are referring to when they say “I want to patent this!” It may be granted to anyone who invents or discovers any new and useful process, machine, article of manufacture, or composition of matter, or any new and useful improvement thereof.

I get a monopoly to my invention if I get a patent right?

Wrong.  Unfortunately the biggest misconception with patents is that you have the exclusive right to use it.  What you are actually granted under patent law is the right to exclude others from making, using, offering for sale, or selling the invention throughout the United States or importing the invention into the United States” for a limited time in exchange for public disclosure of the invention.  For example, your invention might actually contain components that are protected by another patent.  In order to use your invention, you would have to obtain a license from whoever owns the protected part.

When is an invention patentable?

Your invention must be new and non-obvious in order to obtain a patent.  It must be “new” in the sense that there’s nothing identical out there already.  When analyzing obviousness, the standard used is from the perspective of a “person with ordinary skill in the art.”  In other words, when the USPTO is deciding whether or not to issue you a patent, it will look to the obviousness factor through the eyes of someone who is experienced in the technical field your invention falls under.

How long does a patent last for?

A utility patent lasts 20 years from the date of filing.  By the time a patent issues, you’ll most likely be a couple years into the term already.