Metadata is "data that provides information about other data", but not the content of the data itself, such as the text of a message or the image itself. There are many distinct types of metadata, including:Descriptive metadataThe descriptive information about a resource. It is used for discovery and identification. It includes elements such as title, abstract, author, and keywords.
Structural metadataMetadata about containers of data and indicates how compound objects are put together, for example, how pages are ordered to form chapters. It describes the types, versions, relationships, and other characteristics of digital materials.
Administrative metadataThe information to help manage a resource, like resource type, permissions, and when and how it was created.
Reference metadataThe information about the contents and quality of statistical data.
Statistical metadataAlso called process data, may describe processes that collect, process, or produce statistical data.
Legal metadataProvides information about the creator, copyright holder, and public licensing, if provided.
In the 21st century, metadata typically refers to digital forms, but traditional card catalogs contain metadata, with cards holding information about books in a library (author, title, subject, etc.).
Metadata can come in different layers: This physical herbarium record of Cenchrus ciliaris consists of the specimens as well as metadata about them, while the barcode points to a digital record with metadata about the physical record.
Metadata for a Sphagnum papillosum pot that is part of a common garden experiment at Universität Greifswald
Mass surveillance is the intricate surveillance of an entire or a substantial fraction of a population in order to monitor that group of citizens. The surveillance is often carried out by local and federal governments or governmental organizations, but it may also be carried out by corporations. Depending on each nation's laws and judicial systems, the legality of and the permission required to engage in mass surveillance varies. It is the single most indicative distinguishing trait of totalitarian regimes. It is often distinguished from targeted surveillance.
Certificate of state registration of the "monitoring, control, tracking the target of ground vehicles" – "СAMERTON"
Gratitude of the Department of the Ministry of Internal Affairs of the Russian Federation for the Volkhov region of the organization Perspective Scientific Research Development for the creation of the "CAMERTON" system
RAF Menwith Hill, a large site in the United Kingdom, part of ECHELON and the UKUSA Agreement
Germans protesting against the NSA surveillance program PRISM at Checkpoint Charlie in Berlin