Originally conceived as a showcase of modern and historic computing techniques, the Computing gallery has in recent years become more focused on the historical aspects of early electronic computers.

In 1991 we built the world's first complete Difference Engine No. 2 from plans drawn up by Charles Babbage in the 19th century. In 2000 we built the machine's printer and added it to the Engine.

The Difference Engine No. 2 is surrounded by other Babbage displays, including a portion of the unfinished Analytical Mill and half the great man's brain!

Another fascinating large object in the gallery is the 1956 Ferranti Pegasus – the oldest working computer in the world and one that is switched on and run regularly to the delight of visitors.

A line of wall cases behind the Pegasus detail the early timeline of computer development and also display a selection of calculators and adding machines.

On display

DEC PDP-8 minicomputer, 1965.

The PDP-8 was the first minicomputer. Over 5000 were sold worldwide.

A sectioned Sinclair Executive pocket calculator, 1972.

The first calculator that could really fit into a pocket.

ATLAS circuit board, 1960s.

A piece of fixed store mesh from the Manchester University Computer ATLAS, which was constructed in a joint venture with Ferranti Ltd., becoming available in 1962.