StumbleUpon is a search engine that recommends and directs users to webpages. Users create an account, choose "interests", and then are guided to webpages based on their interests. StumbleUpon allows users to find photos, videos, and other online content that they would not normally see.
Created in 200q, StumbleUpon is the invention of Garrett Camp, Geoff Smith, Justin LaFrance, and Eric Boyd. It was chosen out of a pool of six other company ideas the four creators had come up with.