At the end of the 1970s, IBM was the computer industry’s undisputed leader. It soon realized that microcomputers developed by young Silicon Valley entrepreneurs, such as the Apple II, would eventually eclipse IBM’s mainframes, and so the IBM PC project was launched. However, it soon became clear that the company’s hefty internal processes would prevent it from delivering a microcomputer on schedule. It was therefore decided that various components of the machine could be outsourced using external suppliers. And yet, 50 years ago, Microsoft was just a tiny computer company founded in Albuquerque, New Mexico by two former Harvard students,...