The Airline Transport Pilot Licence (ATPL), or in the United States of America, an Airline Transport Pilot (ATP) certificate is the highest level of aircraft pilot certificate. Those certified as Airline Transport Pilots (unconditional) are authorized to act as pilot in command on scheduled air carrier's aircraft under CFR 14 Part 121.
Airline and commercial pilots fly and navigate airplanes or helicopters. Airline pilots fly for airlines that transport people and cargo on a fixed schedule. Commercial pilots also fly aircraft for charter flights, rescue operations, firefighting, aerial photography, and crop dusting.
The FAA issues a Certified Flight Instructor Certificate (CFI) and a Certified Flight Instructor - Instrument (CFII or CFI-I) add-on certificate. For your initial flight instructor certificate, the check ride is done with an FAA examiner. For the add-on instrument certificate, any designated examiner will do.
A private pilot is the holder of a private pilot license. With a private pilot license (PPL), a pilot is allowed to fly aeroplanes of the category and class that the license designates, in addition fly a category and class airplane up to 12,500 pounds.
Recently, the sport pilot certificate has sort of replaced the recreational pilot certificate, although the recreational license is still available to student pilots. The restrictions on a recreational pilot are greater than those imposed upon a sport pilot or private pilot.