Invention patent fall into four general  types: 

1. Utility patents, usually referred to as "patents" without any further qualification,
2. Design patents which  cover the ornamental appearance of various products, 
3. Plant patents  which cover asexually  reproduced varieties of plants, e.g. hybrid roses, fruit trees bearing new types of fruit, etc., and
4. Semiconductor chip masks which are not called patents but are handled by the Patent and Trademark Office.  

For the grant of an ordinary, or utility patent,  the invention patent must fall into one of four statutory classes of invention, which are

• A process, 
• Machine,
• Article of manufacture,
• Composition of matter, or
• An improvement on an existing invention in one of those classes of invention.

A valid invention patent secures the right to its owner to exclude others from making, using, or selling the claimed invention in the United States and its territories and possessions for a limited period of time. Invention patent go through a number of stages before finally acquiring the much coveted patent. The law recognizes five "rights" periods in the life of invention patent. These five periods in invention patent are:

1. Invention conceived but not yet documented. This is the phase of invention patent when an inventor conceives an invention.
2. Invention documented but patent application not yet filed. After making a proper, signed, dated, and witnessed documentation of in invention patent the inventor has valuable rights against any inventor who later conceives the same invention and applies for a patent.
3. Patent pending (patent application filed but not yet issued). During the invention patent pending period, including the one-year period after a provisional patent application is filed, the inventor can sue and recover damages against anyone who uses the invention. Eighteen months after filing, and while the application is pending, the U.S. Patent and Trademark Office (USPTO) will publish the application unless the applicant files a Nonpublication Request at the time of filing and doesn't file for invention patent outside the U.S.
4. In-force patent (patent issued but hasn't yet expired). After the patent issues, the owner of the invention patent can bring and maintain a lawsuit for patent infringement against anyone who makes, uses, or sells the invention without permission.
5. Patent expired. After the patent expires, the owner of invention patent has no further rights, although infringement suits can still be brought for any infringement that occurred during the patent's in-force period, as long as the suit is filed within the time required by law. An expired patent remains a valid "prior-art reference" forever.