Southwest Airlines entered the airline industry in 1971 with a low-cost business model. It marketed an affordable and fun brand using humor and a heart logo. Southwest grew significantly by offering low fares, frequent flights, free checked bags, and reliable on-time arrivals. It maintained a low-cost structure through the exclusive use of Boeing 737 aircraft, secondary airports, short routes, and basic meals. Southwest also employed humor and promotions to build brand awareness while implementing price discrimination and market penetration pricing strategies.