A patent is a complex document explaining how to make and how to use an invention including detailed drawings, so that someone skilled in the technology would actually be able to make and use the invention. It includes the technical field of the invention, the unique features and advantages, and a summary abstract. Most importantly, the patent document contains legally binding claims which determine the extent of the rights of the patent holder as you can see from how do you patent an idea with InventHelp article.
The patent application, which is made to the US Patent and Trademark Office and to the patent offices of other countries if desired, must include the patent document as described in the previous paragraph, a declaration that you believe yourself to be the true inventor, information about the inventor, a transmittal letter, and the filing fee (currently $385 for individuals or companies with fewer than 500 employees for not more than 20 total claims, including not more than three independent claims).
While it is possible for an inventor to write and file a patent application, it is highly recommended to have the application written (especially the legally binding claims), filed and prosecuted before the US Patent and Trademark Office by a registered patent attorney or agency with years of experience, such as InventHelp patent agency. This may be the single most important component of your success or failure with your invention to enable you to license the invention and prevent others from infringing on your idea.
Your investment in your patent protection (far less than the cost of putting a single advertisement in a national magazine) will pay for itself a thousand times over during the twenty year term of the patent. Without a well written patent you may lose everything.