Wikipedia defines a Document Management System (DMS) as a computer system ( or a set of computer programs) used to track and store electronic documents and/or images of paper documents.
If you want to store documents away- never to be looked at again - then get a brown cardboard box, fill it with paper, seal it up with tape, and store it in the basement- and in 20 years when you move- open it up- and finally decide to throw it out. Rather extreme case in point. Because if you really have documents that you will never have the need to look at again- shred them now.