Each page on the Web has a unique address called a Uniform Resource Locator (URL).
The URL gives you a general idea of where the resource originates and
who is responsible for creating it. The address also hints at the
type of resource and whether or not it will be of value to you.
Let's look at the following sample URL, which is the address for the University
Libraries' laptop computer policies.
- All Web addresses begin with http
which stands for HyperText Transfer Protocol,
the set of standards used by computers to transfer hypertext files (Web
pages) over the Internet.
- This section identifies the computer on which the Web page
is located. From this information, you can determine the entity supporting the computer, and the type of organization it represents.
- www indicates that this computer is acting as a Web server.
- ua is an abbreviation for the University of Alabama.
- lib indicates that this is a library Web page.
- The last part of the domain (in our example .edu) is called the 'top-level domain.'
This tells us what type of organization is running the computer.
- Below are four major categories of Web sites that can be distinguished by the
- .edu = educational institution
- .gov = government site
- .org = organization or association
- .com = commercial enterprise
There are other less common top-level domains as well, such
as .mil (military) and .net (network access provider).
You will also occasionally see two-letter codes at the end of the domain. These
are country codes, which have been assigned to identify and locate
files stored on host computers in countries around the world. Some
- .ca = canada
- .uk = united kingdom
- .de = germany
- .mx = mexico
- .au = australia
If you wish, you may see a complete list of these country
- The last part of the URL is the path. The domain has identified one computer out of the
millions of computers connected to the Internet, but it's the path that pinpoints one specific file
on that computer.
- In our example, the path is policies/laptop.htm. This
tells us that we are looking in a directory (or folder) on the host computer
called 'policies' and that the filename is 'laptop.'
- The .htm is known as a file extension and tells us what type
of file it is. In this case, it's a hypertext file (Web page).