What Is URI (Uniform Resource Identifier)?

Why It Matters

The URI vs URL distinction is a common source of confusion in web development. For domain forwarding, you’ll almost always be working with URLs. But understanding the relationship helps when reading technical documentation about HTTP and redirects.

URI vs URL vs URN

Concept	Tells You	Example
URI	How to identify a resource	Any of the below
URL	How to locate a resource	https://example.com/page
URN	How to name a resource	urn:isbn:0451450523

              URI
             /   \
           URL   URN

Every URL is a URI. Every URN is a URI. On the web, you almost exclusively deal with URLs.

URIs in HTTP

HTTP headers technically refer to URIs, not URLs:

GET /blog/post HTTP/1.1          ← Request-URI
Host: example.com

HTTP/1.1 301 Moved Permanently
Location: https://new.com/blog   ← URI in Location header

The Location header in a redirect response contains a URI — in practice, always a URL.

For Domain Forwarding

When you configure a redirect in Domain Forward, you’re mapping URLs:

• Source: https://old-domain.com/*
• Destination: https://new-domain.com/*

Both are URLs (and therefore URIs). The distinction doesn’t change how you configure forwarding.