By now, everybody has seen an Internet address at least once. Internet addresses can sometimes be confusing. This tutorial will help you decipher those complicated looking Internet addresses.

BACKGROUND:

The Internet addresses that will be discussed in this tutorial are called DOMAIN NAMES. Examples of domain names are:

www.microsoft.com

www.advanced.org/thinkquest

mail.somewhere.com

news.somewhere.com

x2ftp.oulu.fi

Domain names were created to make finding a particular site easier. Before domain names, Internet users had to type out long numeric I.P. addresses to find a particular site. Examples of I.P. addresses are:

127.0.0.1

231.53.452.222

142.645.214.321

Although every computer on the Internet has an I.P. address, not every computer has a domain name. To obtain a domain name a person must pay a yearly fee to register the domain name with a company called InterNIC

TRANSLATING DOMAIN NAMES INTO I.P. ADDRESSES

When you type a domain name into your web browser your computer passes it to a computer on the internet called a DOMAIN NAME SERVER or DNS for short. The DNS will look up the domain name and return the correct I.P. address to your computer. Your computer will then use that I.P. address to connect to the site you requested.

DECIPHERING DOMAIN NAMES

A domain name has several parts to it. For this example we will take apart a simple domain name:

www.microsoft.com

This domain name has three parts that are separated by dots.

SUFFIX

The part on the far right tells what kind of site this is. In this example the ".com" tells us that the site is a commercial site. There are other types of suffixes that can be in a domain name. They are:

.com Commercial. Used by for-profit companies

.org Organization. Used by non-profit organizations

.edu Educational. Used by schools and universities

.gov Government. Used by government agencies

.mil Military. Used by the military

NAME:

The middle part of this domain name is the main part of the name. This is usually the name of the company or organization that owns the domain.

PREFIX:

Most of the time domain names have another name to the left of the name. This usually means that there is more than one computer connected to this domain name. The name on the left is the name of the computer. In this case there is a computer called "www" connected to microsoft.com. This name usually describes what that particular computer does. The purpose of a computer called "www" would be to store web pages.

SITES IN OTHER COUNTRIES

Sometimes, you might see a site with a two letter suffix such as:

x2ftp.oulu.fi

The two letter suffix is a two letter abbreviation for the country that its from. The following lists all the country codes.

ar Argentina

br Brazil

ca Canada

de Germany

fi Finland

...

FILES AND DIRECTORIES IN A WEB SITE

Look at the following example:

www.advanced.org/thinkquest/index.html

It has text following the ".org." This tells your browser to look inside a DIRECTORY called "thinkquest" for a file called "index.html"