URL - Uniform Resource Locator

By: Christine Martz

Meaning of URL – “Uniform Resource Locator”, is a string of characters used to represent and identify a page of information on the World Wide Web that is used by an web browser such as Netscape or Internet Explorer to find HTTP, FTP, telnet, gopher and other resources on the Internet.

The first part of the address lets you know what protocol to use. If you were told to visit the URL "ftp://ftp.download.com/readme.txt", you would be using the File Transfer Protocol (FTP) to download the file "readme.txt" from a remote computer. If the URL was "http://10.0.0.1/faq.html", you would be using Hypertext Transfer Protocol to read the document "faq.html" on the Web.

The second part of the address specifies the domain name or the IP address or the where the resource is located. In the above example, FTP was used to retrieve a document called "readme.txt" from a computer or server that has the domain name "download.com". Sometimes a domain name is not registered for an IP Address. In that case you would need to memorize a computer's IP address. In the second example, HTTP was used to locate a document called "faq.html" from a computer whose Internet Protocol address is 10.0.0.1. It is much easier to remember a domain name rather than an IP address when typing out URLs.

The concept of a URL was introduced in late 1990. At that time, it was called a hypertext name or document name.

Other Related Definitions:

“…If you've been surfing the Web, you have undoubtedly heard the term URL and have used URLs to access HTML pages from the Web. It's often easiest, although not entirely accurate, to think of a URL as the name of a file on the World Wide Web because most URLs refer to a file on some machine on the network. However, remember that URLs also can point to other resources on the network, such as database queries and command output. ” [Sun Microsystems"] 

“…The browser uses the various parts of the URL to find the host, connect to it, retrieve the path portion of the URL, and display the page. The first step is to convert the hostname into an Internet address. The hostname may be descriptive (that is its purpose), but it is also worthless in terms of making an actual connection. Converting a hostname to an address is often referred to as the "address resolution phase". The status bar of your browser may display something like "looking up hostname" during this process. ” [Mark C. Reynolds - WebDeveloper.com] 

“…URIs are not necessarily resolvable in a browser; that is, they may refer to a resource that is not a location on the Web. A URL is a form of a URI (in fact, in current practice, all namespace URIs are URLs), but a URI is--you guessed it--more abstract.” [Frank Willison - O'Reilly Media] 

“…Web addresses were relatively obscure a dozen years ago, but now they appear not just in Web browsers but also on business cards and brochures, on billboards and buses and T-shirts. They're commonly known as Uniform Resource Locators or URLs.” [Dan Connolly - World Wide Web Consortium] 

“…A Uniform Resource Locator (URL) is a compact representation of the location and access method for a resource located on the Internet. Each URL consists of a scheme (HTTP, HTTPS, FTP, or Gopher) and a scheme-specific string. This string can also include a combination of a directory path, search string, or name of the resource.” [Microsoft Corporation] 

Related Links:

URIs, URL's, URN's - Overview, History, Significance and Standards.
A Guide to Understanding URLs - Working with Uniform Resource Locators on the Internet
URL Tutorial - Uniform Resource Locators explained
What is a URL? - Lesson: Working with URLs 

Technical Resources:

URLs: Smart resource identifiers - URLs as smart resource names
URI Schemes - Official IANA Registry of URI Schemes
Naming and Addressing: URIs, URLs - Naming and Addressing: URIs, URLs
Uniform Resource Locators - This document specifies an Internet standards track protocol for the Internet community

Products and Solutions:

Xenu's Link Sleuth - Find broken links on web sites with this software
URL Manager - URL Manager software organizes and categorizes favorite URL's

Books About:

Weaving the Web: The Original Design and Ultimate Destiny of the World Wide Web - by Tim Berners-Lee
Web Application Architecture: Principles, Protocols and Practices - by Leon Shklar, Richard Rosen

See Also:

Other URL Resources
 

(C) Copyright Birds-Eye.Net, All rights reserved.
It is against the law to reproduce this content or any portion of it in any form without the explicit written permission of Birds-Eye Network Services, LLC. Federal copyright law (17 USC 504) makes it illegal, punishable with fines up to $100,000 per violation plus attorney's fees.