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 existing hardware production. MCP is still in use today in the Unisys ClearPath/MCP line of computers. UNIVAC, the first commercial computer manufacturer, produced a series of EXEC operating systems. Like all early main-frame systems, this batch-oriented system managed magnetic drums, disks, card readers and line printers. In the 1970s, UNIVAC produced the Real-Time Basic (RTB) system to support large-scale time sharing, also patterned after the Dartmouth BC system. General Electric and MIT developed General Electric Comprehensive Operating Supervisor (GECOS), which introduced the concept of ringed security privilege levels. After acquisition by Honeywell it was renamed General Comprehensive Operating System (GCOS).