During Ada Lovelace’s lifetime, no complete Analytical Engine was built.
Charles Babbage began developing the general-purpose mechanical computer around 1833, after work on the Difference Engine suggested that a more flexible machine was possible. The Analytical Engine was designed to include a “mill” for arithmetic, a “store” for memory, punched-card input, conditional branching, loops, and printed output.
Babbage’s plans were remarkably advanced, but construction never reached completion. Funding problems, disputes with his engineer Joseph Clement, manufacturing limitations, and the enormous complexity of the design all contributed. Babbage continued refining the machine, but Ada died in 1852 without seeing a working Analytical Engine.
Later efforts produced only partial sections. Babbage’s son Henry built part of the mill and printing apparatus in the late 19th and early 20th centuries, but this was not a complete, programmable computer. Ada’s famous Bernoulli-number algorithm therefore could not be tested on the intended machine during her lifetime. Modern reconstructions and simulations have demonstrated how the design might have operated.