Absolute urls, relative urls, and...?

Here are the URL components:

http://www.example.com/en/public/img/logo.gif
\__/   \_____________/\_____________________/
 #1     #2             #3

1. scheme/protocol
2. host
3. path

A URL is called an absolute URL if it begins with the scheme and scheme specific part (here // after http:). Anything else is a relative URL.

A URL path is called an absolute URL path if it begins with a /. Any other URL path is called a relative URL path.

Thus:

• http://www.example.com/en/public/img/logo.gif is a absolute URL,
• ../../public/img/logo.gif is a relative URL with a relative URL path and
• /en/public/img/logo.gif is a relative URL with an absolute URL path.

Note: The current definition of URI (RFC 3986) is different from the old URL definition (RFC 1738 and RFC 1808).

The three examples with URI terms:

• http://www.example.com/en/public/img/logo.gif is a URI,
• ../../public/img/logo.gif is a relative reference with just a relative path and
• /en/public/img/logo.gif is a relative reference with just an absolute path.

I have seen it called a root relative URL.

From the Microsoft's documentation about Absolute and Relative URLs

A URL specifies the location of a target stored on a local or networked computer. The target can be a file, directory, HTML page, image, program, and so on.

An absolute URL contains all the information necessary to locate a resource.

A relative URL locates a resource using an absolute URL as a starting point. In effect, the "complete URL" of the target is specified by concatenating the absolute and relative URLs.

An absolute URL uses the following format: scheme://server/path/resource

A relative URL typically consists only of the path, and optionally, the resource, but no scheme or server. The following tables define the individual parts of the complete URL format.

• scheme - Specifies how the resource is to be accessed.

• server - Specifies the name of the computer where the resource is located.

• path - Specifies the sequence of directories leading to the target. If resource is omitted, the target is the last directory in path.

• resource - If included, resource is the target, and is typically the name of a file. It may be a simple file, containing a single binary stream of bytes, or a structured document, containing one or more storages and binary streams of bytes.