While paper is still used, its usage is decreasing. While we're leaving a boatload of archeological remains in terms of infrastructure, the amount of literary data we're leaving physically is decreasing. Let's say something turns our modern digital media useless, would future historians be able to use our literary sources to build a picture of our political (to say one example of where literary sources are very useful) history? If so, how accurately?
Hello !
Now this is my time to shine ! Some background first : although I have an historical formation and degree, my job today is as an archivist. Meaning, the people who make sure the historians of tomorrow will have something to study in the first place (or try to).
Basically, my job could be divided in three parts, all equally important and, I hope, relevant to your question.
The first one is selecting which documents to keep and try to preserve for centuries. Sorting them, trying to evaluate what will be important in 200 years and more to understand how we live today. So we're doing some historical pre-work, so to speak, trying to extract relevant informations and document from a gigantic load of datas. It is not as tedious as it sound, because we have a good idea of what will be useful in the future. For most documents (be they digital or hard copies), we know what to do with them. But there is still a lot of room for appreciation, personnal expertise and sensibility and, of course, improvement. Now keep in mind we're not the only ones doing that. People do it on their own, and there is some kind of "natural process" to sort things that will be kept through time.
The second one is making sure we can still read the information in 200 years (this is an arbitrary duration). First of all : hard copies. You may or may not know that, in fact, paper is quite fragile. It does not like heat, nor cold, nor humidity, nor dryness. It needs to be kept somewhere around 20°C and 50% humidity as much as possible to survive long periods of time. Keep in mind we're talking about centuries, millenias even. We aim to keep the documents ready to read for millenias. There are a lot of conditions to be respected (even the sun ruins writings on paper, and light too) to make sure this is possible, but that's what we do.
Now for digital documents. Some of them do have a hard copy, to begin with,be it because the document was originally on paper and digitalized or because it was printed later on. To put it simply : digital documents are a pain to keep functionnal. Paper is fragile, yet well kept it can endure millenias. No hard drive, no CD, no floppy disk, no VHS can. The general solution is servers. Secured, access controlled servers. That way, if one of the central units that constitute the server fails (and they do), it does not really matter. The information is copied on multiples units and the afiling ones are replaced. Even if a bomb was to fall on the server room, documents would be safe because we have a second server room acting as a copy that has to be at least 100km away. That is, of course, the best case scenario. A company or a public service acutely aware of the necessity of preserving archives and willing and able to invest quite a lot of money on an electronical archive service. Most companies and administrations don't, at least yet. They store informations on their own servers, but I know for a fact that they generally make saves of those servers at regular intervals on magnetic bands. Not perfect, but beter than nothing.
An overlooked part of keeping electronical documents ready to use is the file format. Yeah, sure, everyone can read a .docx today. But will we be able to in 200 years ? And what about that specific format used by a professionnal program designed for architects. Sure, they can read it. But what about people who will come to the archives after ? And what about 200 years from now, when all operating systems will have changed dramatically and all the format we use may have vanished ? There are already, today, documents we cannot read anymore. Very old formats and such. Do you even own anything able to read a VHS ? Now imagine that with tens of differents materials : VHS, negatives, microfilms, floppy disks and others more complicated, more obscure.
Our solution is to make copies and conversions. Making sure, as much as we can, that our collections are kept in readable formats. Narrowing the scope of authorized formats in our collections to a few, widely spread and if possible open formats. That way, we can make conversions, time after time if need be, and will be able to do so for millenias. Or so we hope.
The third one, finally, is about formation and sensibilization. Telling employees how they should deal with their documents. Explaining them that, if possible, we'd rather have them save their documents in this format and not this one. Explaining them that no, your handwritten note about the discussions in the executive committee are not going to the bin, put that down or I'll have to become violent. Help them keep their papers (or the digital equivalent) in order, easy to navigate and find when the need arises.
I hope I answered your question, feel free to ask any detail !