Y Combinator Management, LLC (YC) is an American technology startup accelerator and venture capital firm launched in March 2005 which has been used to launch more than 4,000 companies. The accelerator program started in Boston and Mountain View, expanded to San Francisco in 2019, and was entirely online during the COVID-19 pandemic. Companies started via Y Combinator include Airbnb, Coinbase, Cruise, DoorDash, Dropbox, Instacart, Reddit, Stripe, and Twitch.

Airbnb, Inc. is an American company operating an online marketplace for short- and long-term homestays and experiences. The company acts as a broker and charges a commission from each booking. The company was founded in 2008 by Brian Chesky, Nathan Blecharczyk, and Joe Gebbia. Airbnb is a shortened version of its original name, AirBedandBreakfast.com. Airbnb is the most well-known company for short-term housing rentals.