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.