Part 61 is the counterpart to Part 91. Part 61 is concerned with the licensing and certification of pilots seeking a single, multi-, or commercial license. It also defines the certification of flight instructors, ground instructors, airline transient pilots, and student pilots. Like all the other chapters in the FARs, Part 61 has its own rules and requirements that must be met and followed in order to successfully complete training. It gives detailed prerequisites for getting your license. In fact, one of the few things not covered in Part 61 is the certification of pilots for instrument flight, or IMC certification.
Unlike Part 91, Part 61 does not deal with the standards of charter or airline operations for aircraft but instead deals with requirements for the pilots flying those aircraft, although charter and airline pilots can originate from a Part 61 school. Part 61 is no less than dedicated to the standards of human performance in aviation, whereas Part 91 also incorporates standards for companies and their aircraft. Schools might choose to teach Part 61 or Part 91 because of less stringent standards. However, there are more time requirements for Part 61. Smaller flight schools not associated with universities or colleges will probably be teaching under Part 61 due to the freedom it gives to teach. It allows for smaller businesses to share the flying experience with future pilots without having to possess the creditability of a university such as Embry Riddle Aeronautical University in Daytona Beach.
There are colleges, however, that operate under Part 61. For example, Daniel Webster College in Nashua, NH is a Part 61 operating college. They run a program that is more lax and deals strictly with the certification of pilots. Since instrument flying is not covered in Part 61, it is not taught at Daniel Webster.
Along with pilot ratings, one can receive helicopter ratings, rotorcraft ratings, balloon ratings, crop dusting ratings, tail wheel plane endorsements, and a recreational pilot's license. It also covers things like second in command requirements and category II and III aircraft certification, as well as required certificates and logbook endorsements.