Digital preservation is a great way to take analog information and transform it into easily storable digital information. Doing this will make it easier for others to access that information as well as preserve it for future generations long after the originals have ceased to be functional for viewing.
One of the main strengths of digital preservation is how diverse it is in terms of what you can actually store. It started out with books and text-based objects a couple of decades ago, but nowadays you can pretty much store anything you want in digital format for later use.
Images are digitally preserved all the time. Photographs that were taken with typical optical film cameras can be scanned into a digital format like JPEG or BMP. Diagrams can be scanned in exactly the same method. The average basic household scanner can be purchased today for less than $50 in some cases, allowing just about anyone with important pictures they’d like to back up to actually digitally preserve those pictures.
Even multiple pages can be digitally preserved over the course of a short period of time. Typical digital preservation inputs can now actually mean scores of different books available in digital format. If you doubt this, all you have to do is take a quick look at Google Books and you will quickly see that even books that are centuries old have been preserved in digital format. Other online ventures like the free Project Gutenberg have also greatly advanced the lines of digital preservation, taking many rarely read older books and manuscripts and making them available online.
Although storage incompatibilities and technological obsolescence are things that can be viewed as problematic for digital preservation, it is clear that the benefits greatly outweigh the drawbacks. As a result, you should definitely consider starting to get all of your non-digital data into a digitally preserved format.