Without Paypal, there would be no YouTube.

Back in February 2005, three former Paypal employees - Chad Hurley, Steve Chen, and Jawed Karim - got together to develop an online video platform using their their own money and old Paypal connections. The inspiration for what would be known as YouTube came from Paypal's business model - a payment button that would take you directly to the Paypal site could be embedded for billing on anyone's website.

The trio initially thought this idea could be applied in a video format simply to improve online sales and auctions, but it soon became a much larger beast which spanned generalized video streaming! After only a year of existence, YouTube was acquired by Google for $1.6 billion, and the online world would never be the same.
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Check out the first YouTube video!.