There are 3 types of patents: utility, design and plant. Design patents cover new and ornamental aspects of items of manufacture. An iPhone® smart phone or a Corvette® sports car are great examples of design patents. These have a life of 14 years from the date the patent is granted.
Plant patents are a particular type of patent that are directed to anyone who has invented or discovered and asexually reproduced a distinct and new variety of plant. Plant patent protection extends 20 years from the date of filing.
Utility patents are known to most people and cover articles of manufacture, methods of manufacture, compositions of matter, and business methods, typically used in the software and banking sectors. One subset of utility patents is provisional patents. These are the foot-in-the-door patent applications that last for one year from the filing date and provide you with an additional year of protection if a patent issues. A provisional application may be a more informal document but should contain all of the information regarding your invention.
A utility patent must be useful, novel and non-obvious. Non-obvious means that a fictional person of ordinary skill in the art pertaining to your invention could not combine published relevant references to come up with your invention. A utility patent has a life of 20 years from the date of filing. However, once a patent is granted, maintenance fees must be paid to the US Patent and Trademark Office before 3.5, 7.5 and 11.5 years after issue, or the patent will expire.
Information relating to patents may be found at the following sites: