Glossary of Metadata Terms

ONIX - The ONIX family includes XML-based standards for Books, Serials, and Licensing Terms & Rights Information. ONIX for Books is the international standard intended to support computer-to-computer communication of book industry product information. EDItEUR coordinates development of ONIX standards.

Standard Address Number (SAN) - a unique seven-digit identifier signifying addresses of organizations involved in the publishing industry. SANs are used in electronic communications to accurately identify participants in commercial transactions.

Stock Keeping Unit (SKU) - a number or code used to identify each distinct product or service for sale, allowing businesses to track inventory and product availability. SKUs are often used to refer to different versions of the same product. Unlike ISBN and other nationally and internationally standardized identifiers, SKUs are usually assigned at the merchant level.

Structured Data - resides in fixed fields within a record or file. The metadata in ONIX files and records is structured data. Although data in XML files are not fixed in location like traditional database records, they are nevertheless structured because the data are tagged and can be accurately identified. In contrast, unstructured data is generally free-form text such as that found in word processing documents, web pages, and email messages.

Universal Product Code (UPC, UPC-12) - a unique numerical identifier for machine-readable encoding, currently used exclusively in barcodes. UPC is used mainly for media-music, movies, and video games, for example. ISBN is the required identifier encoded in book barcodes, but mass-market paperbacks may also carry a barcode encoded with UPC because they are commonly sold in outlets such as supermarkets, drugstores, and big-box chain stores.

XML (Extensible Mark-Up Language) - XML was designed to structure, store, and transport data electronically, whereas HTML (Hypertext Markup Language) was designed to facilitate web-based display of information. XML was designed to promote usability over the internet and is the most common tool for data transmission between applications. For example, XML-based formats have become the default for many office productivity tools, such as Microsoft Word and Apple's iWork. Information carried in standards created using XML format, such as ONIX, can be understood by most business partners and systems involved in publishing and bookselling.