Look up at the top of this web page. Above the page
you will see the "location bar" of your
web browser, which should contain something very
like this:
http://www.boutell.com/newfaq/basic/url.html
This is the Uniform Resource Locator (URL) of the
web page you are looking at right now. A URL can
be thought of as the "address" of a web
page and is sometimes referred to informally as
a "web address."
URLs are used to write links linking one page to
another; for an example, see the HTML entry.
A URL is made up of several parts. The first part
is the protocol, which tells the web browser what
sort of server it will be talking to in order to
fetch the URL. In this example, the protocol is
http.
The remaining parts vary depending on the protocol,
but the vast majority of URLs you will encounter
use the http protocol; exceptions include file URLs,
which link to local files on your own hard drive,
ftp URLs, which work just like http URLs but link
to things on FTP servers rather than web servers,
and mailto URLs, which can be used to invite a user
to write an email message to a particular email
address.
The second part of the example URL above is the
fully qualified domain name of the web site to connect
to. In this case, the fully qualified domain name
is www.boutell.com. This name identifies the web
site containing the page. The term "fully qualified
domain name" refers to a complete web site
or other computer's name on the Internet. The term
"domain name" usually refers only to the
last part of the name, in this case boutell.com,
which has been registered for that particular company's
exclusive use. For more information about registering
domain names, see the setting up web sites entry.
The third part of the example URL is the path at
which this particular web page is located on the
web server. In this case, the path is /newfaq/basic/url.html.
Similar to a filename, a path usually indicates
where the web page is located within the web space
of the web site; in this case it is located in the
basic sub-folder of the newfaq folder, which is
located in the top-level web page directory of our
web site.
