Alexis de Tocqueville Institution it called "hybrid" source models, in which true open source code is mixed with proprietary code, with the result that intellectual property rights are nullified. To illustrate potential problems with this approach, the book cited the case of Linus Torvalds, creator of Linux. It claimed Torvalds used source code taken from Minix, a small Unix-like operating system used in teaching computer science, to create Linux 0.01, on the theory that no mere student could write an entire Unix-like kernel single-handedly — although writing a kernel of similar size and capabilities is a standard part of many computer science degrees. These
Operating system paging capabilities, provided personal computers with the ability to run multitasking operating systems like those of earlier minicomputers and mainframes. Microsoft responded to this progress by hiring Dave Cutler, who had developed the VMS operating system for Digital Equipment Corporation. He would lead the development of the Windows NT operating system, which continues to serve as the basis for Microsoft's operating systems line. Steve Jobs, a co-founder of Apple Inc., started NeXT Computer Inc., which developed the NEXTSTEP operating system. NEXTSTEP would later be acquired by Apple Inc. and used, along with code from FreeBSD as the core of Mac