A computer environment that supports multiple users simultaneously. The term originated in the 1960s when multiple terminals were first connected to a single mainframe, allowing programmers and students simultaneous access to computing resources. Today's networks of servers within the enterprise or throughout the Internet provide a similar computing model, with hundreds or thousands of users accessing the same server or cluster of servers at the same time.
The major difference today is that users have their own computers that perform a great deal of the processing, mostly to render the user interface but often to perform some or all of the business processing. The terminals in the 1960s and 1970s were primarily keyboards and screens. See
cloud computing and
dumb terminal.