Khan Academy history (https://en.wikipedia.org/wiki/Khan_Academy): The organization started in 2004 when Sal Khan tutored one of his cousins on the Internet using a service called Yahoo Doodle Images. After a while, Khan's other cousins began to use his tutoring service. Because of the demand, Khan decided to make his videos watchable on the Internet, so he published his content on YouTube.[9] ...The critical acclaim and the positive responses of students prompted Khan to quit his job... and focus on the tutorials