YouTube is the world's most popular and frequently visited video streaming website. The site's users watch about four billion hours of video per month and upload more than 70 hours worth of video every minute.
YouTube officially launched in November of 2005. A group of former Paypal employees founded it as an independent startup, and Google purchased it in November of 2006. Prior to Google's purchase of the company, much of its funding came from Sequoia Capital.
In its early days, YouTube operated above a Japanese restaurant in San Mateo, California. The company has since moved to a state-of-the-art facility in San Bruno.
YouTube's first uploaded video was titled "Me at the zoo." Co-founder Jawed Karim created and uploaded the video, which shows his visit to the San Diego Zoo. The video remains available on the site.
YouTube's popularity originally came from independent user-generated content. While that remains an important part of the site's appeal, the company has added corporate partners such as CBS and MGM as it has grown. These partners make full-length shows and movies available through the site.
According to one of the site's software engineers, about 30 percent of the videos on the site account for 99 percent of the traffic. Music videos from popular artists such as Justin Bieber and Psy account for much of the site's traffic.