Design Patent

• A design patent is protection on the industrial design of a product. The underlying product may not be an original idea, but a unique design or rendering is eligible for a design patent. A prime example of a product that while an extension of an existing idea but having a patent protected design is the Apple iPad. A design patent last for 12 years.
  
  

Provisional Patent

• The provisional patent is a precursor to a non-provisional patent. The provisional patent lasts 12 months and is designed to protect new and in development ideas. If an inventor has an idea, but has not fully fleshed out the details, he can apply for the provisional patent and within the next year upgrade to a full non-provisional patent.
  
  

Non-provisional Patent

• A non-provisional patent is the most common form of a patent issued in the United States. To apply for a non-provisional patent, the applicant need only provide a mechanical drawing, and a description of the product. After paying the fee and getting an approval, the non-provisional expires in 20 years.
  
  

Agricultural Patent

• Agricultural patents cover genetically modified plants and seeds used in crop growing combines. An agricultural patent has a legal life of 20 years.