Taxi time is the total time of an aircraft's movement on the ground. Taxi time can be the time it takes an aircraft to go from a hangar or terminal to the runway until cleared for takeoff, or the aircraft's going from exiting the runway back to the hanger or terminal. It is used by pilots to determine various kinds of information pertinent to the flight, such as fuel burn, total fuel loss, weight, takeoff weight, landing weight, and true airspeed. Since weight plays a huge part of whether an aircraft can take off or land, the amount of time a plane spends burning fuel on the ground can greatly alter the plane's takeoff or landing distances.
It also plays a role for the companies that own the planes. Nobody likes to spend the majority of their flight stuck in an airplane on the ground waiting to take off. As a result, companies try to minimize their taxi time as much as possible for the benefit of both the customer and themselves by reducing the amount of time the passenger spends on the plane and saving money due to the reduced fuel burn. Charter jets usually have shorter taxi times. The planes need less force to move due to their lighter weight and have lower takeoff speeds, allowing them to be off the ground faster. The super-mid-sized jet and very light jet are perfect examples of both larger and shorter aircraft.
Air-traffic control also has an investment in taxi time. The shorter an aircraft's taxi time is, the faster air-traffic control can get planes in and out of the airport. It is in both the best interests of the pilots and the controlling agency to expedite traffic in and out of the airport as fast as possible, and they do this by having efficient taxiways and shorter taxi times. In larger airports, there tend to be more runways, allowing for the takeoff of many aircraft at one time.