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The term evolved in the 1960s to describe the "small" third generation computers that became possible with the use of transistor and core memory technologies. They usually took up one or a few cabinets, compared with mainframes that would usually fill a room. The first successful minicomputer was Digital Equipment Corporation's 12-bit PDP-8, which cost from US$16,000 upwards when launched in 1964.
As microcomputers developed in the 1970sMillennia: 1st millennium 2nd millennium 3rd millennium Centuries: 19th century 20th century 21st century Decades: 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s Years: 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 Events and trends and 80sMillennia: 1st millennium 2nd millennium 3rd millennium Centuries: 19th century 20th century 21st century Decades: 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s 2030s Years: 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Events and trends, minicomputers filled the mid-range area between low powered microcomputers and high capacity mainframes. At the time microcomputers were single-user, relatively simple machines running simple program-launcher operating systems like CP/M or DOSThe acronym DOS stands for disk operating system, a type of operating system for computers that provides the abstraction of a file system resident on hard disk or floppy disk secondary storage. DOS for IBM PC compatibles In particular, DOS refers to the f, while minis were much more powerful systems that ran full multi-user, multitasking operating systems like VMS and UnixUNIX (or Unix is a portable, multi-task and multi-user computer operating system originally developed by a group of AT&T Bell Labs employees including Ken Thompson, Dennis Ritchie and Douglas McIlroy. Unices The term Unices includes Unix and Unix-like ope. The classical mini was a 16-bitIn computer science, 16-bit is an adjective used to describe integers that are at most two bytes wide, or to describe CPU architectures based on registers, address buses, or data buses of that size. Prominent 16-bit processors include the Intel 8086, Inte computer, while the emerging higher performance 32-bit32-bit is a term applied to processors, and computer architectures which manipulate the address and data in 32- bit chunks. It is also a term given to a generation of computers where 32-bit processors were the norm. The range of integer values that can be minis were often referred to as superminis.
The 7400 series of TTL integrated circuits started appearing in minicomputers in the late 1960s. The 74181 Arithmetic and Logic Unit was commonly used in the CPU data paths. Each 74181 had a bus width of four bits, hence the popularity of bit-slice architecture. The 7400 series offered data-selectors, multiplexers, three-state buffers, memories, etc. in dual inline packages with one-tenth inch spacing making major system components and architecture evident to the naked eye. Starting in the 1980s, many minicomputers used VLSI (Large and Very Large scale Integration), often making the hardware organization much less apparent.
Today at the turn of the millennium few minicomputers are still in use, having been overtaken by Fourth Generation computers built using a more robust version of the microprocessor technology that is used in personal computers. These are referred to as " servers", taking the name from the server software that they run (typically file server and back-end database software, including email and web server software).
The decline of the minis happened due to the lower cost of microprocessor based hardware, the emergence of inexpensive and easily deployable local area network systems, and the desire of end-users to be less reliant on inflexible minicomputer manufacturers and IT departments / "data centers" – with the result that minicomputers and dumb terminals were replaced by networked workstations and PCs in the latter half of the 1980s.
During the 1990s the change from minicomputers to inexpensive PC networks was cemented by the development of several versions of Unix to run on the Intel x86 microprocessor architecture, including Solaris, Linux and FreeBSD/ NetBSD. Also, the Microsoft Windows series of operating systems now includes server versions that support preemptive multitasking and other features required for servers, beginning with Windows NT. Significantly, Windows NT was written largely by designers from DEC who were responsible for the DEC VMS operating system, originally developed for the VAX minicomputer range in the 1970s. Also, as microprocessors have become more powerful, CPUs built up from multiple components, once the distinguishing feature differentiating mainframes and midrange systems from microcomputers, have become increasingly obsolete, even in the largest mainframe computers