A minicomputer was a type of computer which was an intermediate stage in the development of computers from the original mainframes to the later, and current, microcomputers used in personal computers and embedded systems.
Minicomputers marked not just a technical development, but also an economic and organizational one. Mainframes were extremely large and expensive machines, and typically only the largest organizations had more than one. This had repercussions in both the kinds of tasks such computers were used for, and the organizational frameworks set up for their use.
With the appearance of minicomputers, which although less capable, were much less expensive, computers could be used for other applications (such as process control), and computers could be acquired by small groups, moving their control down in organizational hierarchies, towards more local control.
The first 'proto-minicomputers' were the LINC and the PDP-5 (the predecessor of the later PDP-8, which is widely considered to be the firat true minicomputer). Digital Equipment Corporation gained its foothold as a producer of minicomputers; its later PDP-11 minicomputer was at one point the best-selling computer (in terms of units) in the world.