One may hear the terms “system patent”, process patent, method patent, product patent or device patent. These are not different types of patents; rather, these names refer to the subject matter that is defined in the claims of a utility patent. Therefore, if the subject matter of a utility patent pertains to a method of doing something, then it may be called a method patent, colloquially, while it is really no different than any other utility patent.
All utility patents are directed to such things above which are useful and which are functional. There is no limit to the number of different areas of invention, and, typically it is limited only by imagination, need and the like.
Some examples of utility patents include mechanical devices (a medical device, a bag or a box, a brake caliper, a hanger, etc.), electrical devices (i.e., improvement to a toaster, a microwave, a sensor, solar panels, etc.), electronics (i.e., power supply, circuitry improvements, radio antenna designs, etc.), methods or processes (i.e., extracting improvements with the extraction of gold from ore, removal of sulfur from hydrocarbon fuel), a system (i.e., several machines together for welding automotive assemblies, etc.), software features (swipe to unlock, pull down to refresh, etc.). Generally, these include all types of inventions that have functionality.
In many instances, the above types can be intertwined within a single application. For example, a patent may be directed to a device and a method of making the device. In another example, a patent may be directed to a device and a method of using the device. In another example, a patent may be directed to a chemical composition and a system that can be utilized to create the chemical composition. Often processing equipment patents cover the process and a system that is made to carry out the process.