The National Archive.

The National Archive at Kew is a fascinating place. You can view such records as the passenger list from the Titanic to the muster roll for Nelson's Victory to cabinet papers and released  official documents.
I've mentioned some of the records I've viewed in other blogs, war diaries from World War One, operational records from World War Two, also the divorce papers of my Grandmother from 1921 and some of my Uncle's Merchant Navy documents one of my Grandad's Royal Navy records and the other Grandad's army records and also the passenger list noting one of my Great Aunt's when she sailed from Liverpool as a 'Military dependant third class' in 1919 after she'd married a Canadian soldier.
There's a process, a slow process of gradually digitising all the records. This will take years and years. Emphasis was put on digitising the regimental war diaries from WW1 to coincide with the centenary of the war for easy access for researchers. I'd already looked at some of these before this was started. You request the record using it's record number and eventually a bod puts the item in a  sort of cubby hole with your seat number on. It's from here that you collect the records  and take them back to your place. Open the box and there you have the original  documents probably written out just a few yards from the front line, if not in the front line. Another case of what I call touching history.
You'll lose all this of course as records do become digitised but it must be better to protect the original documents. If you go to Kew you can view any record free of charge, you can photo them, without flash again for free. Printed copies you have to pay for. You can go on line and download, for a charge  records already digitised, though it's interesting to note when I was researching one of Tara's family who served in the Australian army. As his records were all in Oz I had no alternative but to view and download on line but the Australians do not charge anything at all!  British government please note!
If you want to visit to see records  you must apply for a readers ticket. You need to take along two items identifying yourself with your address as well, then you answer some bone headed questions on their site, questions like: 'Would you write on the records?'  Put yes to that & I don't think you'd get a readers ticket! Security is taken seriously as it should be. You can only take in pencils to write with and all in a clear plastic bag that they supply, there's also staff who check you in and out of the reading rooms who look through anything you are taking with you to make sure there is no pilfering of the records. They also run talks and guided tours behind the scenes and have regular exhibitions. it's a very interesting place to visit.