It's kind of funny. The machine viewed as the first PC is the Altair 8800, released in 1975. It was not much more than a box of switches. However, 2 years earlier, Xerox had developed a PC with a screen, mouse, keyboard, and even a GUI! This was not done again until Apple released the Lisa, a decade later! Imagine what would have happened if Xerox had marketed their Alto computer. We would have skipped right over DOS and Apple would probably have gone out of business a long time ago. Microsoft wouldn't have even been created! I just think that the Alto is not given enough credit. I bet somebody was fired from Xerox the day the Macintosh was released!