While preserving recorded information and ensuring the transmission of knowledge from one generation to another is an ancient cultural activity, as a field within library and archival science, preservation is only a few decades old. It began primarily as item-level repair and conservation, deriving its original professional traditions and physical techniques in large part from the museum world. To the importance in that world of the repair and conservation of individual pieces deemed to be of special value as artifacts, preservation in libraries has added the significance of the archival value of the object as bearer of historical evidence. In a very short time, preservation has developed into a critically important part of managing a library's most precious assets, its collection. Paradoxically, dedicated as it is to mitigating the deleterious effects of aging, preservation has rapidly become, along with computer applications, one of the most forward-looking fields in the library and archival profession.
When all data are recorded as 0's and 1's, there is, essentially, no object that exists outside of the act of retrieval. The demand for access creates the "object," that is, the act of retrieval precipitates the temporary reassembling of 0's and 1's into a meaningful sequence that can be decoded by software and hardware. A digital art-exhibition catalog, digital comic books, or digital pornography all present themselves as the same, all are literally indistinguishable one from another during the storage, unlike, say, a book on a shelf.