The term applies equally to printed materials, such as books and periodicals, as well as to audiovisual materials and microforms. Duplicate copies are reported as one title. The World Book Encyclopedia would be 1 title and 26 physical units. Six copies of the same book would be 1 title and 6 physical units. A packet containing six audio tapes of a book would be one physical unit.
Books are nonperiodical printed publications bound in hard or soft covers, or in loose-leaf format.
Serials are publications issued in successive parts, usually at regular intervals, and as a rule, intended to be continued indefinitely. Unbound serials are counted as volumes when the library has at least half of the issues in the publisher s volume. This includes audiocassettes, audiocartridges, audiodiscs, audioreels, talking books, and other sound recordings. Materials in electronic format are physical units such as CD-ROMs, magnetic tapes and magnetic disks that are designed to be processed by a computer. Excluded are bibliographic records used to manage the collection, library system software, and microcomputer software used only by the library staff Video materials are materials on which pictures, sound, or both are recorded.