What types of things can be patented? How?

As a broad general statement, any useful item that meets the requirements for a patent and hasn't already been invented can be patented. Some processes can also be patented. Check the list of patents granted by the U.S. Patent and Trademark Office on their web site: USPTO.gov There are also a number of books for sale and in libraries that will give you a better idea of what qualifies.

Patentable Subject Matter Requirement - 35 U.S.C. ? 101: Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title. Judicial exceptions (non-patentable subject matter): Laws of Nature Natural Phenomena Abstract Ideas These exceptions are "part of the storehouse of knowledge of all men . . .free to all men and reserved exclusively to none.