BBC WW2 People's War

For the Second World War specifically, this is a good, interactive website where you can contribute to - and search - an archive of wartime memories. There is also good advice about how to pursue any family history research relating to this period. There is an excellent equivalent on the First World War (www.bbc.co.uk/history/war/wwone), though inevitably, given the scarcer records, it is less full of detail. Note that where it refers to the PRO records, these are now of course, in the National Archives.