The HP 2100 was a series of minicomputers produced by Hewlett-Packard (HP) from the mid-1960s to early 1990s. The 2100 was also a specific model in this series. The series was renamed HP 1000 by the 1970s and sold as real-time computers, complementing the more complex IT-oriented HP 3000, and would be the starting point for a line of desktop computers. They would eventually be phased out in favor of UNIX-based RISC workstations.
HP entered the minicomputer market in 1966, along with Varian Data Machines. Later, General Automation, Computer Automation, Data General, Micro Systems, and Lockheed would also be competitors. The 2116A was the first model of the series. It was designed by HP's Dymec division, after absorbing Data Systems Inc. (DSI), a subsidiary of Union Carbide. DSI had designs for a 16-bit minicomputer called the DSI-1000, which would eventually evolve into the 2116A through HP's involvement.
Read more about HP 2100: 2116A Overview, 2100 Series Architecture, Descendants and Variants, Instruction Overview