Airliner

An airliner also called a commercial transport is a large fixed-wing aircraft for transporting passengers and cargo. The largest airliners are wide-body aircraft jets. These aircraft are frequently called twin-aisle aircraft because they generally have two separate aisles running from the front to the back of the passenger cabin.

Such planes are owned by airlines. These smaller airliners are generally used for medium-distance flights with fewer passengers than their wide-body counterparts. Mounting the engines in under wing pods also makes physical access for maintenance quicker and easier compared to tail-mounted engines.

Additionally, low wing design helps keep the engine nacelles and refueling valves closer to the ground to simplify access and the wing's surface acts as a barrier to prevent the engines' noise from reaching the fuselage in-flight. A smaller, more common class of airliners is the narrow-body aircraft or single aisle aircraft. 

Airlines and their partners sometimes use these for short flights between small hubs, or for bringing passengers to hub cities where they may board larger aircraft. Members of this class of aircraft normally lack such amenities as lavatories and galleys and typically do not carry a flight attendant as an aircrew member.