The Poor Man's Patent is a Myth
One of the undying myths of Patent World is that there is such a thing as a Poor Man's Patent. If you've never heard of it, the poor man's patent involves writing out a description of your invention and mailing that description to yourself. The transmission of this description through the mail and the cancelling of the postage by the Post Office is supposed to establish a date of invention for you. That way if someone steals your invention or comes along and invents it independently, you have "proof" that you invented it first. The proof is in the sealed envelop and the date the postage was cancelled.What Does Useful Mean?
The patent law specifies that inventions must be useful, which means have a useful purpose. Being useful also includes operativeness, meaning that an invention must operate or perform its intended purpose.Non-Provisional Application
Although you can convert a provisional application into a non-provisional application, the USPTO recommends filing a separate non-provisional application that references the earlier provisional one. Doing so can extend the time your invention is protected by up to one year. A non-provisional application includes a lengthy written document with a description of your invention and all the things you claim you invented, as well as drawings, an oath or declaration and fees for the filing, research and examination of the application. The USPTO recommends using a registered patent attorney to draft and file your non-provisional application. USPTO regulations include specific requirements for the format of applications and the necessary drawings -- and examiners reject applications that don't meet these requirements.More on Prior Art
Remember, while patent searching is a big part of prior art , it is not everything. If someone has made your invention before you without patenting that still counts against your patentablity. A complete search for prior art might include for example: searching non-patent literature such as any magazine, newspaper, or trade paper article written about inventions like yours also a complete search would include international patent documents (online) and not just those found at the USPTO. Do not make the mistake of believing that just because no one else is selling your product that it does not already exist. After determining that your idea is patentable and qualifies for a patent - you now need to decide if the expense of patenting is worth it.What You Can Patent
A patent provides you with the right to keep others from making and selling your invention for up to 20 years. The most common type of patent, a utility patent, protects rights in new and useful processes, machines and other things. These patents also can protect rights in non-obvious improvements made to existing things. To determine if your invention is patentable, you must first research all previous patents and other publicly disclosed inventions to ensure that no one else has already patented something similar. Because this process can be difficult and complicated, the U.S. Patent and Trademark Office recommends hiring a registered patent attorney to conduct the search for you.