At Xerox's Palo Alto Research Center, research had already been underway for several years to create a new humanized way to organize the computer screen, today known as the desktop metaphor. Steve Jobs visited Xerox PARC in 1979, and was absorbed and excited by the revolutionary mouse-driven GUI of the Xerox Alto. By late 1979, Jobs successfully negotiated a payment of Apple stock to Xerox, in exchange for his Lisa team to receive two demonstrations of ongoing research projects at Xerox PARC. When the Apple team saw the demonstration of the Alto computer, they were able to see in action the basic elements of what constituted a workable GUI. The Lisa team put a great deal of work into making the graphical interface a mainstream commercial product.