URI or URL

On the internet, URLs stands for Uniform Resource Locators, and URIs stands for Uniform Resource Identifiers.

According to W3C’s definition:

"…a URL is a type of URI that identifies a resource via a representation of its primary access mechanism (e.g., its network "location"), rather than by some other attributes it may have. Thus as we noted, "http:" is a URI scheme. An http URI is a URL. The phrase "URL scheme" is now used infrequently, usually to refer to some subclass of URI schemes…"

According to another resource, it seems more sense to me:

"URI stands for Universal Resource Identifier and URL stands for Universal Resource Locator. Often times people use the terms interchangeably, which is not entirely correct. A URL is a subset of the URI popular protocols. These are protocols (http://, ftp://, mailto:). Therefore all URLs are URIs. The term URL is deprecated and the more correct term URI is used in technical documentation. All URIs are means to access a resource on the Internet and are a a technical short hand used to link to the resource. URIs always designate a method to access the resource and designate the specific resource to be accessed."

In conclusion, always trying to use URI for your reference…