Apple's history is the stuff of investors' dreams and inventors' hopes. From its humble start in a garage in 1976, the company's initial public offering four years later was the biggest since Ford (F) shares started trading in 1956. This year, Apple became the second most valuable company behind Exxon. Today, Apple's (AAPL) must-have devices and broad following among consumers make it a key player in mobile phones, computers, tablets, digital music players, and digital media distribution. It wasn't always so. While the company's early computers, especially the Apple II line, brought the world of personal computing into offices, homes, and schools, there were more than a few bad apples. Even fans groan at the memory of the Pippin and the QuickTake camera. The Apple III and Lisa were personal computer bombs. Apple TV still hasn't quite caught on. Lately, however, the company has made few missteps. Its latest game-changer is the iPad, which made its debut in April 2010. The iPad may end the personal computer era that Steve Jobs helped introduce 30 years ago.