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Descriptive metadata— the descriptive information about a resource. It is used for discovery and identification. It includes elements such as title, abstract, author, and keywords
Structural metadata— metadata about containers of data and indicates how compound/complex objects are put together, for example, what formats data exists in and how the data is structured into containers or folders. It describes the types, versions, conventions, relationships and other characteristics of digital materials
Administrative metadata— the information to help manage a resource, like resource type, permissions, and when and how it was created, when it was last updated.
Reference metadata— the information about the contents (such as references, citations ) and quality of data
Statistical/Process metadata, also called process data, may describe processes that collect, process, or produce data
Legal/Ownership metadata— provides information about the creator, copyright holder, and public licensing, if provided.
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