Patents are part of the intellectual property landscape along with copyrights, trademarks and trade secrets. A patent is a legal and technical document that gives the owner the right to exclude others from making, using or selling their inventions for a limited period of years. You can let someone practice your invention through licensing (you still own the patent and collect a royalty) or assigning the patent to them (you give up ownership).
There are three main types of patents.
Drawings - illustrations of the invention; essential features usually indicated by reference numbers
Background - helps to explain what is known about the technical field at the time of filing; usually written without legal or technical jargon
Summary - summarizes the invention and explains how it solves the problem(s) identified in the background
Detailed Description - describes the invention in sufficient detail to enable a skilled person to perform the method and/or produce the product disclosed in the patent; may define certain terms used elsewhere in the patent
Claims - most important part of patent - they define the legal scope of the invention; all patents must include at least one claim