Metadata
The term metadata is relatively new and only emerged with the commercial use of computer and information technology, and thus with the storage of data and its analysis and archiving. However, the principle of reference and formal specifications inherent in the term “metadata” has been library practice for centuries. A current example of metadata is, for example, a book: while for the reader the content of the book is the actual data, the year of publication, author and the number of the current edition constitute the metadata. Metadata contains information about the characteristics of certain data, but without naming the content of the data itself. This characteristic explains the frequent use of metadata for the description of information resources, in order to make these better discoverable (e.g. in a library). Furthermore metadata are used for the production of relations between individual materials.
Metadata in statistics in software development
Metadata is used in statistical databases to represent, for example, municipal directories, industry and occupational designations, and other data. Statistical metadata also includes descriptions of data such as survey forms. Metadata also plays a major role in software development. For example, for documentation or code generation, use in universal software, or as a record definition in a database.
Storage of metadata
The storage of metadata can be divided into different areas: First, there is the storage of metadata in the document itself. In an HTML document, for example, metadata is used to specify the author, language, company, and keywords. Furthermore, metadata can be stored in an associated reference work, for example in a library catalog. The third possibility of the storage of metadata is, as far as it concerns computer files, the storage in the file attributes (different data over computer file, which do not belong directly to contents of the respective file). Most file systems allow only specified metadata to be stored in file attributes, while other file systems allow any metadata to be associated with a file.
