Southwest Airlines has grown since 1967 to become one of the largest low-cost carriers in the world through a strategy of cost leadership, differentiation, and focus. It keeps costs low by operating a single aircraft type, using secondary airports, and having an average of three cabin crew. Southwest differentiates by offering fun experiences, pets on flights, and bag-free travel. The company focuses on serving price-sensitive and convenient travelers with frequent, reliable flights on shorter routes comparable to driving times.