Uniform Resource Identifier - unambiguous reference to a resource (which can be anything, really)
URI is short for Uniform Resource Identifier. It’s a generalization of the concept of a “URL”. Whereas a URL refers to a Location on the internet, a URI unambiguously refers to a generic resource. This could be a website, or simply a dataset, image, or anything else.
URIs function like UUIDs, but typically have a more hierarchical structure. They also must exist within a given Namespace.