Appendix B: What's a URL?

A URL (Uniform Resource Locator) describes the location of a web page, image, sound, or any other document on the World Wide Web. It is sometimes called the web address of a document (see Appendix G for how to create links using a URL). URL's can describe a document's location in two ways:

As an absolute or inclusive location (Absolute URL)
Relative to the current location (Relative URL)

An absolute URL has the form (Things in parentheses are optional and if omitted, default values are assumed.):

protocol://serverName(:port)/directory/(documentName)

Example:

http://www.yahoo.com/Internet/Providers/index.html

Divided up into its parts it looks like:

Protocol (how information is exchanged):	http
Web Server Name:	www.yahoo.com
Port (server connection number):	DEFAULT VALUE
Directory:	/Internet/Providers/
Document Name:	index.html

When making links on a web page, certain parts of the URL may be omitted. When omitted they are assumed to be the same as the current page (where the clickable link appears). A URL with omitted parts is called a Relative URL.

• doc-one.html - The web page named doc-one.html on the same server in the same directory as index.html
• my-folder/doc-two.html - the document named doc-two.html found in the subdirectory my-folder on the same server as index.html
• /some-folder/doc-three.html - the document named doc-three.html found in the directory /some-folder on the same server as index.html

Here are some examples of URL's and their associated parts:

Absolute URL's

Relative URL's

(CURRENT indicates values from current document and do not need to be entered as part of the URL)

If the URL's in the above table were the target of hotlinks on the web page

      http://www.hccweb.com/library/index.html

• http://www.hccweb.com/community/index.html
• http://www.hccweb.com/manual/
• http://www.hccweb.com/library/myDoc.html