Preserving digital objects is a complex problem to which scholars have responded with numerous techniques and strategies. Files which we build and use today will be obsolete before we realize it and the machines which read them will be trash as well.
One of the earliest strategies for preserving digital objects was to periodically refresh them. This process, called conversion, means converting the file formats which are out of date to newer ones, which can be accessed on the latest computers. The technique of refreshing is tedious, requiring periodic work ad infinitum.
Another technique for preservation is emulation. Emulation means building a machine which can mimic an old machine and thereby read old file formats, effectively ressurecting what would otherwise be a useless file. However, emulation requires access to old technology which is sometimes difficult.
One technique, proposed by Raymond Lorie, was to adopt a Universal Virtual Computer posthaste which would be able to recognize files and their formats. If this UVC were integrated into every file format and every machine, things could be preserved indefinitely. The scope of this suggestion provides immense difficulty.
Virtual machines, such as the Java Virtual Machine, seem to offer a glimmer of hope for the immediate future. However, the JVM remains unproven, and its tenability remains to be seen. The JVM is the best technique for the present, but we can only hope for better in the future.
References:
Lorie, R. Long Term Preservation of Digital Information. JCDL, '01,
June 24-28, Roanoke, VA.