Midrange computer
Midrange computers, or midrange systems, are a class of computer systems which fall in between mainframe computers and microcomputers.
The class emerged in the 1960s and machines were generally known at the time as minicomputers - especially models from Digital Equipment Corporation (PDP line), Data General, Hewlett-Packard (HP3000 line and successors), and Sun Microsystems (SPARC Enterprise). These were widely used in science and research as well as for business.
IBM favored the term "midrange computer" for their comparable, but more business-oriented, System/3, System/34, System/32, System/36, System/38, and AS/400 ranges, which are now represented by the IBM i.
Since the 1990s, when the client–server model of computing became predominant, computers of the comparable class are instead usually now known as servers to recognize that they usually "serve" end users at their "client" computers.
Midrange systems are primarily high-end network servers and other types of servers that can handle the large-scale processing of many business applications. Although not as powerful as mainframe computers, they are less costly to buy, operate, and maintain than mainframe systems and thus meet the computing needs of many organizations. Midrange systems have become popular as powerful network servers to help manage large Internet Web sites, corporate intranets and extranets, and other networks. Today, midrange systems include servers used in industrial process-control and manufacturing plants and play major roles in computer-aided manufacturing (CAM). They can also take the form of powerful technical workstations for computer-aided design (CAD) and other computation and graphics-intensive applications. Midrange system are also used as front-end servers to assist mainframe computers in telecommunications processing and network management.