  Not a rock group, not a geology database, but “data about data”. Are we allowed to say “data about data”? Find out in Jeromy Caballero’s extended definition: The term metadata is most frequently used in connection with technology. However, its most general definition is simply data about data. Mark Taylor, an editor with the Global Spacial Data Infrastructure Association (GSDI), has said: "Metadata is the term used to describe the summary information or characteristics of a set of data. This very general definition includes an almost limitless spectrum of possibilities ranging from human-generated textual description of a resource to machine-generated data that may be useful to software applications.
"1 Library Trends offers this definition: "Metadata is the value-added information that documents the administrative, descriptive, preservation, technical, and usage history and characteristics associated with resources. "2 In this sense, metadata is anything from the name and address on a stamped envelope to special tags describing a packet of information traversing the Internet. Metadata could even be background information providing context for an article or a story. Taylor also describes metadata as something that allows knowledge about data to persist from user to user. For example, as people leave an organization, knowledge about certain data might be lost if that data is undocumented.1 But if metadata—additional information describing that data—is attached to the data, knowledge of the data’s use and value can be preserved for future users. Therefore, metadata can be defined as an interoperability enabler, providing an environment in which two systems can work together by making data from each system usable by the other system.
The metadata is the common context in which the systems can cooperate and work with the same data. "The application of metadata is critical in the digital environment," observes Library Technology Reports, "because it allows a digital object or collection to be understood by both machines and humans in ways that promote interoperability. "3 However, not only does metadata create context for interoperability, but it serves as a transmission/communication enabler that facilitates packaging, transmitting, routing, receiving, interpreting, and applying data over the Internet. Metadata accompanies all the data that crosses the Internet, allowing it to be correctly transmitted and correctly used when it reaches its destination, wherever that destination might be. Because of the wide variety of data that crosses the Internet, and because its potential destinations are often unknown, the metadata that accompanies data transmitted over the Internet is complex and must account for a large array of possible uses. This metadata is difficult to incorporate into an information system that expects very specific, tailored metadata.
"The metadata required to describe the highly heterogeneous, mixed_media objects on the Internet," observes Library Trends, "is infinitely more complex than simple metadata for resource discovery of textual documents through a library database. "2 According to InfoWorld, the data that crosses the Internet is being collected by data stores at its destination, but the metadata is often being discarded as unuseable by those data stores. New methods of creating metadata that serves both to transmit the data and to effectively catalogue it in an information management system are the inevitable result.4 This is the type of metadata that "provides the underlying foundation upon which digital asset management systems rely to provide fast, precise access to relevant resources across networks and between organizations. "2 Not only do organizations need data to be transmitted, they need data to be efficiently catalogued and easily retrievable. Information Management Journal offers this definition of metadata: "Traditionally, the term `metadata' has been widely used to characterize the descriptive information that will support search and retrieval of both paper and electronic material. Over the past three or four years the use of the term metadata has expanded to include additional information that must be acquired and retained in order to effectively manage electronic records over long period[s] of time, including permanently.
"5 Metadata is a storage and retrieval facilitator that enables organizations and even groups of organizations to catalogue, archive, and access data accurately and effectively in information management systems. Data entered into a database, for example, is accompanied by metadata describing that data in many different ways. This metadata allows the data to be searched and retrieved in a variety of contexts. Finally, metadata can be defined as a supplemental resource for data. "Metadata is needed to describe both external and internal characteristics of the resource," explains Library Journal. "External metadata explains and maintains those critical relationships among different versions of the same content.... Internal metadata allows for the description of the content of the resource at the desired level of granularity.
"6 When a video camera records a segment of footage, for example, it might also record supplemental information such as the time, the pan, angle, amount of light, and so forth. This information is metadata by dint of its accompanying the actual footage and being data about data. In a book, supplemental data is often gathered in an appendix, and data about the overall contents of the book is gathered in an index. In these cases, the data establishes the context in which the metadata has value, not the other way around. Sources: 1 http://www.gsdi.org/pubs/cookbook/chapter03.html 2 Hunter, Jane L. "A Survey of Metadata Research for Organizing the Web. " Library Trends, 00242594, Fall2003, Vol.
52, Issue 2. 3 "Applications of Metadata. " Library Technology Reports, Sep/Oct2002, Vol. 38 Issue 5, p60. 4 InfoWorld, 11/10/2003, Vol. 25 Issue 44, p38.
5 Baron, Jason R. "Recordkeeping in the 21st Century. " Information Management Journal, 15352897, Jul99, Vol. 33, Issue 3. 6 Thomas, Judith. "Digital Video, the Final Frontier. " Library Journal, 03630277, Winter2004 Net Connect, Vol.
129. 
