Pixar began in 1979 as part of the Lucasfilm computer division, known as the Graphics Group, before its spin-off as a corporation in 1986, with funding from Apple co-founder Steve Jobs, who became its majority shareholder. Disney purchased Pixar in 2006 at a valuation of $7.4 billion by converting each share of Pixar stock to 2.3 shares of Disney stock. Pixar is best known for its feature films, technologically powered by RenderMan, the company's own implementation of the industry-standard RenderMan Interface Specification image-rendering application programming interface. Luxo Jr., a desk lamp from the studio's 1986 short film of the same name, is the studio's mascot.