YouTube is an American online video sharing platform headquartered in San Bruno, California. The service, created in February 2005 by three former PayPal employees – Chad Hurl, Steve Chen and Joe Karim – was acquired by Google in November 2006 for $ 1.65 billion and is now operating as a subsidiary of the company. YouTube is the second most visited website after Google search, according to Alexa rankings on the Internet.

YouTube allows users to upload, view, rate, share, add to playlists, report, comment on videos, and subscribe to other users.Unregistered users can watch, but not upload, videos on the site, while registered users can upload an unlimited number of videos and add comments. Age-restricted videos are available only to registered users affirming themselves to be at least 18 years old.As of May 2019, there were more than 500 hours of content uploaded  each minute and one billion hours of content being watched every day. YouTube and selected creators earn advertising revenue from Google AdSense, a program that targets ads according to site content and audience.