Beneath their personal rivalry—and occasional grudging respect—was their basic philosophical difference. Jobs believed in an end-to-end integration of hardware and software, which led him to build a machine that was not compatible with others. Gates believed in, and profited from, a world in which different companies made machines that were compatible with one another; their hardware ran a standard operating system (Microsoft’s Windows) and could all use the same software apps (such as Microsoft’s Word and Excel).
