English inventor who worked with Charles Wheatstone (Wheatstone, Sir Charles) in developing electric telegraphy (telegraph).

Cooke's attendance at a demonstration of the use of wire in transmitting messages led to his experimentation in 1836 with telegraphy. Soon afterward, he and Wheatstone, who had also worked with the telegraph, formed a partnership.

In 1837 they were granted their first patent, but the cost of their model made it impractical. A quarrel between them over credit for the invention was settled amicably in 1841 but flared again a few years later. Wheatstone is generally considered the more important of the two in the history of the telegraph, but Cooke contributed a superior business ability. Their most important invention, an electric telegraph using only one magnetic needle instead of several, was recognized by patent in 1845. Cooke was knighted in 1869 and granted a civil-list pension in 1871.