A professional who classifies library materials, such as books, audiovisual materials, and periodicals, according to subject matter. Responsibilities include:

• Reviews materials to be classified and searches information sources, such as book reviews, encyclopedias, and technical publications to determine subject matter of materials.
• Selects classification numbers and descriptive headings according to Dewey Decimal, Library of Congress, or other classification systems.
• Makes sample cards containing author, title, and classification number to guide onsibilities incl in preparing catalog cards for books and periodicals.
• Assigns classification numbers, descriptive headings, and explanatory summaries to book and catalog cards to facilitate locating and obtaining materials.
• Composes annotations (explanatory summaries) of material content.