Firstly, Ada King, Countess of Lovelace
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Widely regarded as 'the first programmer' Ada Lovelace worked with Charles Babbage in his Creation of the Analytical Engine. She developed a program that, had it been built, would have calculated er, something mathematical*
Secondly, Rear Admiral Grace Hopper
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She was one of those people who, in military research offices, grappled with punchcards and valves, trying to harness the power of computers the size of houses with the processing capability of digital watch. she was also rather senior in the US navy. odd that.
and lastly, Hedy Lamarr
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the co-inventor of the Spread Spectrum - a way of protecting radio signals from being intercepted or corrupted - used in anything wireless these days.
-Ben
*I'm interested in this sort of thing, but that doesn't mean I understand it in the slightest. I'm a humanities graduate with rather limited interests, sorry.