analytical engine

Programmable computing device designed by English mathematician Charles Babbage in 1833.

It was based on the difference engine but was intended to automate the whole process of calculation. It introduced many of the concepts of the digital computer but, because of limitations in manufacturing processes, was never built.

Among the concepts introduced were input and output, an arithmetic unit, memory, sequential operation, and the ability to make decisions based on data. It would have required at least 50,000 moving parts. The design was largely forgotten until some of Babbage's writings were rediscovered in 1937.