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Uniform resource identifier

(also URI)

Uniform resource identifier definition

A uniform resource identifier (URI) is a character sequence that identifies a physical or logical (abstract) resource connected to the internet. The resource does not always have to be connected to the internet to get identified. With uniform resource identifiers, internet protocols can facilitate interactions between these resources. The uniform resource identifier uses the string of characters incorporated in it as identifiers. For example, it can use a file path or a scheme name to identify resources. A uniform resource identifier can identify a few types of resources, including webpages, electronic documents, images, and information sources that have a consistent purpose.

See also: URL injection, digital identity

Uniform resource identifier elements

  • Scheme. The first element of a uniform resource identifier is the scheme name. It is case-insensitive and split from the rest of the object with a colon.
  • Authority. The authority element of the uniform resource identifier consists of multiple parts – a host with an IP address or a registered name, an optional authentication part, and an optional port number.
  • Query. The query is an optional element of the uniform resource identifier. It contains a string of non-hierarchical data and is typically a sequence of attribute-value pairs. The pairs are divided by a delimiter, like an ampersand or a semicolon.
  • Fragment. The fragment is another optional element of the uniform resource identifier, which contains an identifier that directs a secondary resource. The fragment and the element before it are separated by a hash.