While small low-cost carriers like Allegiant and Spirit began unbundling their fares and charging for checked bags as early as 2007, American Airlines is widely credited as the first major "legacy" carrier to introduce a fee for the first checked bag in May 2008. This move was a response to record-high fuel prices and forever changed the economics of the aviation industry. Within months, United, Delta, and US Airways followed suit. Interestingly, Southwest Airlines famously chose not to follow this trend, launching its "Bags Fly Free" marketing campaign, which remains a core part of its brand identity today. Before 2008, most airlines allowed passengers to check one or two bags for free as part of their ticket price. Today, baggage fees have become a multi-billion dollar revenue stream for the global airline industry, often costing passengers between $30 and $60 per bag on domestic routes.
The Transportation Security Administration is an agency of the United States Department of Homeland Security that has authority over the security of transportation systems within, and connecting to the United States.