The University of North Carolina at Chapel Hill
JOMC 50/EIS Research Initative
This site last updated Oct. 1, 1996, by Tom Hughes.

Anatomy of a Web Address

Click on the above graphic to see an excellent example of the Australian National University Library's "Publishing on the World Wide Web" site at http://info.anu.edu.au/courses/html/demo/ The graphic has been reproduced from Australian National University Library's web-site athttp://info.anu.edu.au/courses/html/demo/demo17.html only for academic discussion, evaluation, research and complies with the copyright law of the United States as defined and stipulated under Title 17 U. S. Code.

Uniform Resource Locator (URL)

A URL is the "address" of a document, image, sound, video clip or other resource on the World Wide Web.

This is a complete URL:

http://www.unc.edu/~daikat/URLparts.html

These are its parts:

Protocol: http
Host name: www.unc.edu
Directory path: ~daikat
File name: URLparts.html

Notice that the file name in this URL has some upper case letters. On the Web, upper and lower case letters in a file name are often treated as different characters, so "urlparts.html" might not work.

URL Scheme: [protocol][host][file]

[protocol]
[host]

[file]
You can end a URL with the name of the Web server, a subdirectory on that computer, or a specific file. File names on the Web genererally end with ".html" or ".htm" or ".txt"
If you do not specify a file name, your Web browser will look for a file named "index.html" in that directory. If it does not find one, it may give you a list of files in the directory.
Netscape can also open a file on your own desktop computer. In this case it is not using http:, and the "Location" field looks like this:

URL Examples

http://www.unc.edu/~daikat/URLparts.html
ftp://ftp.ncsa.uiuc.edu/

In addition to HTTP, many Web sites also use other Internet protocols like MAILTO: and FTP. FTP stands for File Transfer Protocol, and is used to copy a file from one computer to another even if the receiving computer cannot display that file on its screen. FTP can move binary files -- sound clips, executable programs and graphics -- as well as text.
mailto: daikat@email.unc.edu

With Netscape and other Web browsers it is easy to send mail, but harder to check your incoming mail.

HTML Documents & HTTP Servers

Hypertext Markup Language (HTML)

Markup language used by the WWW browser programs for formatting documents on the display, including images, movies, audio, and text.
Also displays links to additional documents on the WWW (or locally).

Hypertext Transfer Protocol (http)

Server program that listens for requests from WWW browsers.
Makes connection, provides information, then breaks connection.
"Browsing" a document for many minutes does not mean you are literally connected to the server for those minutes. The page has been loaded onto the browsing (client) computer.

Forms Processing and the Common Gateway Interface

HTML has markup tags to display fill-out forms with information that is returned to the http server.
The http server in turn has programs that process the information. Such programs, sometimes called Common Gateway Interface (CGI) scripts, can copy information from the forms into a file or database, return requested information from a file or a database, or perform other operations.

This web site is especially for the students enrolled in UNC's JOMC 50 class, as well as for any other interested person. If you have questions or comments, please email one of the following:
Prof. Deb Aikat
Tom Hughes, Teaching Assistant
Eric Chernoff, Internet Student Coordinator