A users' group (also users group or user group) is a type of
club focused on the use of a particular
technology, usually (but not always)
computer-related.User's groups started in the early days of
mainframe computers, as a way to share sometimes hard-won knowledge and useful software, usually written by end users independently of the factory-supplied programming efforts.
SHARE, a user group originated by aerospace industry corporate users of
IBM mainframe computers, was founded in 1955 and is the oldest computer user group still active.
DECUS, the
DEC User's Society, was founded in 1961 and its descendant organization still operates. The
Computer Measurement Group (CMG) was founded in 1974 by systems professionals with a common interest in (mainframe)
capacity management, and continues today with a much broader mission. The first
UNIX user's group organized in 1978.
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