74 Print fixed information on paper in a way that allowed books to exist in space and survive over time. Books are physical entities and the constraints of using information that consists of words fixed on paper and pages that are bound into volumes have framed much of our use of information for several centuries. Libraries, for example, are needed as places for holding books, and they are designed and organized so as to facilitate access to information in print form. Card catalogues are necessary because books occupy a great deal of physical space and each book needs to be represented by something smaller so that there is information about the whole collection in one place. In law, the whole West key number and digest system was a highly creative, albeit labor- intensive, method for dealing with the constraints of information in physical form.
Electronic information is fixed neither in time nor in space.
Information that appears on screen as text or image, or that is presented as sound, is not stored as text, image, or sound. All electronic information is stored in digital form, and it is in its digital form that the information is processed and communicated. It is only when presented to the human eye or ear that the information is transformed into something intelligible to human senses. Ink fixed to a physical surface is the basic condition or form of print. The stability of printed information, the authority of printed information, and the trust placed in printed information derive from this physical condition and from the ability to create multiple copies of an original.