Bletchley Park: they also served
10 November 2013 Last updated at 12:14 GMT
As well as the bravery of those on the frontline, the vital work done behind the scenes during World War Two by those decoding German military plans is also honoured on Remembrance Sunday.
Sophie Raworth met Ruth Bourne and Betty Webb, who trained and worked at Bletchley Park, the nerve centre of the code-breaking operation.
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