Airbnb turned spare rooms and second homes into the world's largest lodging marketplace, with millions of hosts offering stays that hotels cannot replicate. The company takes a service fee on each booking and owns none of the properties, a structure that scales with minimal capital. Supply growth is the perpetual priority, since unique listings in the right cities are what draw guests. Founded in 2008 by design students renting air mattresses, Airbnb expanded into experiences and long-term stays as remote work blurred travel and living.