Los Angeles International Airport (LAX) is one of the most complex and competitive aviation hubs in the world, serving as a primary gateway for several major carriers. Unlike many airports dominated by a single airline, LAX is a "mega-hub" for four of the largest U.S. airlines: American Airlines, Delta Air Lines, United Airlines, and Alaska Airlines. For American, it is a key transpacific and domestic gateway; for Delta and United, it serves as a critical jumping-off point for flights to Asia, Australia, and the South Pacific. Additionally, LAX is a major "focus city" for low-cost carriers like Southwest Airlines and JetBlue, and it serves as a primary hub for the regional carrier SkyWest. Because of its massive international traffic, it is also a vital "gateway" for dozens of foreign flag carriers, often serving as their primary U.S. entry point. The airport's unique layout, with nine terminals, allows these various airlines to maintain significant operations simultaneously. For travelers, this means a high volume of flight options and competitive pricing, but it also results in a very busy environment with complex transfers between terminals, especially when moving between different airline alliances like Oneworld, SkyTeam, and Star Alliance.