They still store certain parts of your military record on microfiche, not all but most. However they're suppose to archive your originals upon discharge. Is the system perfect? Nope.
Any originals would have went to St. Louis, but there was a big fire there some years back and a lot of the paper documents were destroyed by water and smoke. Once a servicemember's service record is closed out, and he or she has no reserve commitment remaining, the record used to be mailed to the NPRC, where it was converted to microfiche.
I'm sure that with advances in technology, they now store the data in a pdf file or some other scanned media. Anything that comes out of there now, is stamped "official copy", including any DD-214 copies that you might request.