HTTP from entry to the ground (4)--uri, URLs, and urns

Uri

URI full Name: Uniform Resource Identifier, Chinese name is Uniform Resource Identifier. Used to identify a resource that uniquely identifies an information on the Internet.

All resources available on the Web, such as HTML, images, videos, and so on, are identified by URIs.

URIs include URLs and urns.

Url

URL Full name: Uniform Resource Locator, Chinese name is Uniform Resource Locator. A URL is a specific URI that is a concise representation of the location and access methods of the resources obtained from the Internet. That is, the general Uri,url can not only identify a resource, but also indicate how to locate the resource.

The URL must be a URI, but the URI is not necessarily a URL.

Urn

Urn Full name: Uniform Resource Name, Chinese name is permanent Uniform Resource Locator. A urn is used as a unique name for a specific content, regardless of where the current resource is located. It exists in order to be able to be found after the resource is moved, however, there is no very mature use plan at present.

The urn must be a URI, but the URI is not necessarily a urn.

HTTP from entry to the ground (4)--uri, URLs, and urns