I am working on a few issues with the agency that I work for. One of which is our handling of older files before they are transcribed. I am running across both .dct files and also (.dau and .ddf). I like the fact that with the .dct I can look at the file and it includes our Clinician name/date , etc. The .ddf/.dau combo doesn't really tell me anything when trying to restore files for users.
What exactly are the differences and why do I have both?