Augusta Ada King-Noel, Countess of Lovelace (née Byron) (10 December 1815 – 27 November 1852) was an English mathematician and writer, chiefly known for her work on Charles Babbage's early mechanical general-purpose computer, the Analytical Engine. She was the first to recognise that the machine had applications beyond pure calculation, and published the first algorithm intended to be carried out by such a machine. As a result, she is sometimes regarded as the first to recognise the full potential of a "computing machine" and the first computer programmer.
Ada was the only legitimate child of the poet Lord Byron, and his wife Anne Isabella Milbanke "Annabella", Lady Wentworth. All of Byron's other children were born out of wedlock to other women. Byron separated from his wife a month after Ada was born and left England forever four months later. He commemorated the parting in a poem that begins, "Is thy face like thy mother's my fair child! ADA! sole daughter of my house and heart?". He died of disease in the Greek War of Independence when Ada was eight years old. Her mother remained bitter and promoted Ada's interest in mathematics and logic in an effort to prevent her from developing her father's perceived insanity. Despite this, Ada remained interested in Byron and was, upon her eventual death, buried next to him at her request. She was often ill in her childhood.
Ada married William King in 1835. King was made Earl of Lovelace in 1838, and Ada in turn became Countess of Lovelace.
Her educational and social exploits brought her into contact with scientists such as Andrew Crosse, Sir David Brewster, Charles Wheatstone, Michael Faraday and the author Charles Dickens, which she used to further her education. Ada described her approach as "poetical science" and herself as an "Analyst (& Metaphysician)".
She died of uterine cancer in 1852 at the age of 36.