They basically invented the consumer PC and perhaps even more crucially were all about networking when DARPANET was in its infancy. They brought the world much closer for both professionals and consumers and for every mistake (Newton) they came back much stronger (iPad).
People will say, oh, but the iPod wasn't the first MP3 player. No, technically it wasn't, but you can't remember what the first was because the iPod changed the game so vastly - especially with the introduction of iTunes - that nobody could really picture using anything else. It reminds me of television: Logie Baird may have demonstrated the first TV, but it was a mechanical system that even then was pushing its natural limits. It took someone with vision like Philo Farnsworth to set the standard that everyone else copied and used for the next 70 years.
It's a rare hybrid of new technology/ideas made user-friendly whilst retaining class-leading aesthetics to the point whereby a company built an entire culture.
Steve Jobs may have once said that he being the richest man in the cemetery didn't motivate him but he built it into the world's second largest company. A company based on ideas and belief rather than being lucky enough to exploit natural resources.
Oh, and Pixar.
