HP 9000 is a line of workstation and server computer systems produced by the Hewlett-Packard (HP) Company. The native operating system for almost all HP 9000 systems is HP-UX, which is based on UNIX System V. The HP 9000 brand was introduced in 1984 to encompass several extant technical workstation models launched formerly in the early 1980s. Most of these were based on the Motorola 68000 series, but there were also entries based on HP's own FOCUS designs. From the mid-1980s, the line was transitioned to HP's new PA-RISC architecture. Finally, in the 2000s, systems using the IA-64 were added. The HP 9000 line was discontinued in 2008, being superseded by Itanium-based HPE Integrity Servers running HP-UX. History The first HP 9000 models comprised the HP 9000 Series 200 and Series 500 ranges. These were rebadged existing models, the Series 200 including various Motorola 68000 (68k) based workstations such as the HP 9826 and HP 9836, and the Series 500 using HP's FOCUS microprocessor architecture introduced in the HP 9020 workstation. These were followed by the HP 9000 Series 300 and Series 400 workstations which also used 68k-series microprocessors. From the mid-1980s onward, HP began changing to its own microprocessors based on its proprietary PA-RISC instruction set architecture (ISA), for the Series 600, 700, 800, and later lines. More recent models use either the PA-RISC or its successor, the HP–Intel IA-64 ISA. All of the HP 9000 line run various versions of the HP-UX operating system, except earlier Series 200 models, which ran standalone applications or the Basic Workstation / Pascal 3.1 Workstation operating systems. HP released the Series 400, also known as the Apollo 400, after acquiring Apollo Computer in 1989. These models had the ability to run either HP-UX or Apollo's Domain/OS. From the early 1990s onward, HP replaced the HP 9000 Series numbers with an alphabetical Class nomenclature. In 2001, HP again changed the naming scheme for their HP 9000 servers. The A-class systems were renamed as the rp2400s, the L-class became the rp5400s, and the N-class the rp7400s. The rp prefix signified a PA-RISC architecture, while rx was used for IA-64-based systems, later rebranded HPE Integrity Servers. On 30 April 2008, HP announced end of sales for the HP 9000. The last order date for HP 9000 systems was 31 December 2008 and the last ship date was 1 April 2009. The last order date for