Acorn Computers Ltd. have been manufacturing computers and writing operating systems since 1978. They shot to fame with their innovative BBC Micro in 1982, which won the Queen's award for achievement. The company received this accolade a second time for their pioneering work into RISC chips, on which their present line of desktop computers are based.
Acorn are a small (on the order of 250 employees) computer company based in Cambridge, England. Their main market is the secondary education sector (i.e., high school), but they have a fair enthusiast following too.
For several years now, Acorn's main products have been based around a RISC processor called the ARM (this used to stand for "Acorn RISC Machine", but since then the bit of Acorn that made the ARM has split off from the main company, and the "A" now stands for "Advanced"). The Risc PC is the latest of these machines. (taken off WWW by Jennifer Green and Gareth McCaughan)

[#] Acorn Corporate Site
[#] Acorn Computer User WWW by Jennifer Green
[#] Acorn FAQ and Machine List by Philip R. Banks

Atom (1981)

The Atom was available as either a kit or ready made machine.

BBC Micro (1981)

The BBC Micro was launched to coincide with a computer literacy drive by the BBC. The machine had possibly one of the best versions of BASIC out of all of the computers at the time and also had good expansion capabilities including networking (Econet), a disc interface, and a second processor.

Electron (1983)

The Electron was launched as a low-cost, slightly cut-down version of Acorn's BBC Micro. It could run most of the same software, but had less expansion capability and ran about 1/3 the speed of it's big brother.

BBC Master 128 (1986)

The BBC Master was an enhanced version of the BBC Micro giving improved features, but sadly also introducing compatibility problems with earlier programs.