Hedy Lamarr ( /ˈhɛdi/; 9 November 1913 – 19 January 2000) was an Austrian-born American actress, celebrated for her great beauty, who was a major contract star of MGM's "Golden Age". Lamarr also co-invented—with composer George Antheil—an early technique for spread spectrum communications and frequency hopping, necessary to wireless communication from the pre-computer age to the present day. Lamarr was born Hedwig Eva Maria Kiesler in Vienna, Austria-Hungary, the only child of assimilated Jewish parents. Her mother, Gertrud (née Lichtwitz), was a pianist and Budapest native who came from the "Jewish haute bourgeoisie", and her father, Lemberg-born Emil Kiesler, was a successful bank director. She studied ballet and piano at age 10. When she worked with Max Reinhardt in Berlin, he called her the "most beautiful woman in Europe". In early 1933 she starred in Gustav Machatý's notorious film Ecstasy, a Czechoslovak film made in Prague, in which she played the love-hungry young wife of an indifferent older husband.