Prepared by: Mahmoud Issa

There is no doubt that the rapid and enormous development and growth in the means and technology of communications had great credit in the spread of information across the globe and beyond, as communication technology provided vast spatial information. The International Information Network (Internet) is one of the most prominent manifestations of the communications revolution in our modern era: this network has made the globe like a single village, rather like a single room, in which data and information are exchanged easily and smoothly. Through it, the researcher obtains the required information, the merchant advertises the commodity he promotes, conversations and knowledge are exchanged, and cultures are transferred between peoples through documents, research, studies, articles, multimedia, and graphics, and news spreads... etc. Since electronic sources represented in documents, research, studies, and articles, which their owners published for free on the International Information Network, are of great importance for spreading knowledge, it was necessary for librarians and those interested in preserving these electronic sources to find a way to preserve them, catalog them, and facilitate the way for users to obtain them, in service also of their basic role in spreading information and knowledge. Librarians went towards achieving their al by applying many library cataloging means, such as: Anglo-American Cataloging Rules 2 (AACR2) and the International Standard Bibliographic Description for Electronic Resources (ISBD.ER), with using the MARC format which is used as a vessel for the cataloging result. They went further to resort to a new format in which the results of the cataloging process are placed, which is the Metadata format. Definition and Concept of Metadata: There are many definitions for metadata, including: Metadata is defined as: descriptive data about electronic and non-electronic data sources, or it is structured information that facilitates the retrieval, use, or management of data and information sources and is molded - i.e., placed - in the metadata format. - Metadata: data to organize information in a correct way, to access it from the International Information Network (Internet). Metadata is also defined as: background data, or data descriptors, where the digital content is described, whether it is an original copy or not, the source of this copy, and how it is organized... etc. - Metadata is a means to organize information so that search engines deliver the required data; it contributes to facilitating access to information, helps in interpreting information, allows the exchange of records between several systems regardless of the type of system or program used, and works on organizing information, especially in the environment of the International Information Network (Internet) in a fast and accurate way. Advantages of Metadata: Metadata works on providing developed structured information that describes, explains, and identifies locations, or makes all that easier for retrieval and use, or manages information sources. This information is not seen by users, but is hidden from them. Some of these advantages can be summarized as follows: 1- Defining the site, what it offers, its capabilities, limits, and characteristics. 2- Assisting search engines scattered on the internet to show the site in a more professional way than relying on the full text of the site, as well as the great speed in that. 3- Effective assistance in cataloging sites for those working in libraries, especially using automated systems and electronic page indices. This cataloging is very useful for both library workers and those in charge of their affairs, in addition to the users of this cataloged data and information. 4- Providing many additional retrieval keys from outside the text to ensure fast and direct access to the data and information contained in the text. 5- Assisting in protecting the intellectual property of the site and ensuring protection of sites from penetration. 6- Facilitating the discovery of related information in terms of subjects, texts, data, or information mentioned in the text. Besides source discovery, metadata can help in organizing electronic sources, facilitating interoperability, and identifying data, information, documents - ... etc. - digitally, as well as supporting archiving and preservation activities. Metadata formats align with descriptive cataloging in many operations, the most important of which are: 1- Facilitating ways to discover the source of data, information, documents, books, maps, etc. 2- Providing the opportunity to discover sources through descriptive and subject access standards. 3- Identifying and determining the location and types of sources that share close and similar subject characteristics. 4- Combining similar sources on the basis of form or content. 5- Distinguishing dissimilar sources. Based on the above, the evaluation of electronic site efficiency must not stop at its external design - of which we may be completely ignorant of its technical characteristics - unless its metadata is revealed and its response to recognized technical standards is observed. Metadata Standards: 1- Dublin Core standard: it contains 15 elements: Title, Creator, Subject, Description, Publisher, Contributor, Date, Type, Format, Identifier, Source, Language, Relation, Coverage, and Rights. Metadata is indicator data, and when we need additional information, we can borrow other indicator data and place them under Dublin Core, provided that they have a mention on the internet, i.e., internationally recognized. For example: data and information regarding payment cards via the internet (Visa card for example) are used in many applications; we take the applications and place them with Dublin Core. Dublin Core applications are used in many works, including: - Determining vernment information sites, all of which use Dublin Core, and they now have 19 elements. - The European Library, which is a gathering that started with eight national libraries in Europe. - International organizations, such as FAO and the UNDP. 2- MARC21 standard: it contains 5 types of data and was named so due to the merger between the US and Canadian systems, and includes books, periodicals, maps, and electronic audiovisual materials... etc. 3- GILS (vernment Information Locator Service) standard. 4- GIS (Geographic Information System) standard. 5- Encoded Archival Description standard. Types of Metadata: There are five types of metadata: 1- Descriptive metadata: describes the source for identification, including keywords, title, author, and abstract... etc. 2- Structural metadata: explains how data elements are grouped together, for example how pages will be requested and displayed to be chapters, or how data elements will be ordered within one page. 3- Administrative metadata: gives information to help manage the source, such as when and how it was created, file type, and other technical information. 4- Rights management metadata: relates to intellectual property rights and how to preserve them. 5- Preservation metadata: contains information required to preserve the source. Metadata Schemes: According to researcher Muhammad Abdul Mawla: 1- Scheme: the term scheme or standard is used significantly to express the format that contains the metadata. 2- Metadata scheme: a set of metadata elements designed for a specific purpose, such as describing a specific type of information sources, including names of description elements and their . A markup language is used to prepare them. Metadata schemes can also be defined simply as structured formats containing data elements and their that describe an information source. Thus, information specialists are not new to dealing with metadata schemes; they deal with MARC21, which is the most prominent example of a metadata scheme.