What is a URN?

URN (Uniform Resource Name) is a unique identifier for a resource on the internet that does not depend on its location. Unlike a URL, which indicates where the resource is located (for example, a website address), a URN serves for the permanent identification of a resource.

Example of a URN:

urn:isbn:0451450523

Here, the URN identifies a book by its ISBN, regardless of where it is stored. URN is used for the unique identification of objects, especially in systems where the permanence of the identifier is important.