Other methods of preserving digital records include migration, preservation of the environment, and emulation.
It is possible to continually migrate documents to a newer format as the older format becomes obsolete, but this process can be time-consuming and repetitive. The National Archives approach to digital preservation involves migration, but escapes the cycle of continual migration. It involves migrating documents in a diverse range of formats to a smaller range of standard formats.
Another approach to digital preservation is to preserve the environment in which the records were created. This is the computer museum approach. It requires keeping and storing superseded computer hardware, operating systems and programs in order to access the records. But maintaining the machines is expensive. And older computers often required highly-trained staff to operate and maintain them.
Emulation combines software and hardware to replicate the performance of another computer of a different design. This technique allows programs or media designed for a particular environment to operate in a different, usually newer environment. Emulation requires the creation of emulators – programs that translate code and instructions from one computing environment so they can function in another. Emulators require people to have detailed knowledge of every aspect of the original systems – and people with those skills are rare. People trying to use the emulated software would also need to be skilled in the use of the original software and operating systems. As new technology is developed, it is very likely that new emulators would need to be developed.