In 2005, Y Combinator developed a new model of startup funding. Twice a year we invest a small amount of money ($14-20k + an $80k note) in a large number of startups (most recently 52). The startups move to Silicon Valley for 3 months, during which we work intensively with them to get the company into the best possible shape and refine their pitch to investors. Each cycle culminates in Demo Day, when the startups present to a large audience of investors. But YC doesn't end on Demo Day. We and the YC alumni network continue to help founders for the life of their company, and beyond.
Since 2005 we've funded over 550 startups, including Loopt, Reddit, Clustrix, Wufoo, Scribd, Xobni, Omgpop, Weebly, Songkick, Disqus, Dropbox, Twitch, Heroku, A Thinking Ape, Machine Zone, Cloudant, Airbnb, Listia, Heyzap, Cloudkick, WePay, Bump, Stripe, CarWoo, Mixpanel, Cardpool, Optimizely, AeroFS, E la Carte, Hipmunk, PagerDuty, Pebble, Meteor, Rap Genius, Codecademy, SocialCam, 42Floors, and Exec.