Databases are used everywhere in modern technology solutions. Databases provide standard means for accessing and manipulating structured data. Structured means that the data components, a.k.a., fields are of specific type (integer, string, and so on) and this knowledge is helpful in querying and manipulating the data.On the other hand, files stored on the file system are generally unstructured and can contain information in any form. Such files and the information they contain are collectively referred to as content. A check image, an email, a manual in PDF format, and a video clip are all examples of unstructured content.
Each content item is associated with some structured data, which describes the content item. This data that provides information about the attached content item is called metadata. Metadata consists of a set of data items called properties or attributes.