A patent for an invention is the grant of a property right to the inventor.
I recommend The Lens because it is easy to use and searches the US Patent and Trademark office as well as patent offices from around the globe.
There are 3 types of patents:
Utility patents may be granted to anyone who invents or discovers any new and useful process, machine, article of manufacture, or composition of matter, or any new and useful improvement thereof.
Design patents may be granted to anyone who invents a new, original, and ornamental design for an article of manufacture.
Plant patents may be granted to anyone who invents or discovers and asexually reproduces any distinct and new variety of plant.