Basic Concepts: Understanding Domain Names & Hostnames
Introduction
When you use the Internet, you use domain name and hostnames
all the time. These hostnames and domain names when put together become the
Internet address that you search with. The domain name without a hostname
is also the most common email address. This article will explore what hostnames
and domain names are and how they are used. We will also discuss TLD's, or
Top Level Domains, such as .Com, .Net, .Org, etc.
Domain Names
Domain Names are the unique name that identifies an entity,
whether that be an single individual or a company, on the Internet. Domain
Names always have 2 or more parts seperated by the dots. The leftmost piece
is the most specific part while the right part is the TLD or Top Level Domain..
Lets disect a domain name so you can see what were are talking about.
Take the domain name bleepingcomputer.com. This
domain name consists of two parts. The leftmost part is the word that identifies
the entity, in this situation its bleepingcomputer. This
is a unique name and there can not be any duplicates on the rest of the Internet
that are used by anyone else. The second part, or the rightmost part is the
TLD, or Top Level Domain. This is .Com which means that it is a commercial
organization.
In the beginning there were only 5 Global TLD's that were recognized
by everyone. These TLD's are discussed below:
-
.com
- This TLD is intended for Commercial business around the world.
- .net
- This TLD is historically and is still used by Internet Service Providers.
- .org
- This TLD is intended to search the noncommercial community.
- .mil
- This TLD is restricted to use by the United States Military.
- .gov
- This TLD is restricted to use by United States Government Agencies.
As the Internet grew and expanded throughout the world, new TLD's were created
to represent different countries. For example the TLD .uk is for the United
Kingdom and .au is for Australia. As more and more domains were registered,
available domain names in the above TLD's were hard to come by. Due to this
more TLD's such as .biz, .info, .name were created to allow more people to register
domain names that fit their needs.
Hostnames
Hostnames can be a confusing as they have a double meaning.
The hostname of an Internet Address is all of the left most pieces of a full
internet address if there are more than 2 parts to the address. If there are
only 2 parts of the address, then the hostname is equivalent to the domain
name.
Here are some examples:
|
Full Address |
Hostname |
Domain Name |
TLD |
www.bleepingcomputer.com |
www |
bleepingcomputer.com |
com |
bleepingcomputer.com |
bleepingcomputer.com |
bleepingcomputer.com |
com |
www.google.net |
www |
google.net |
net |
my.www.bleepingcomputer.com |
my.www |
bleepingcomputer.com |
com |
As you can see from the examples the hostname can be many different
things.
To make things even more confusing, you can refer to the full address in its
entirety as a hostname. For example, with www.bleepingcomputer.com:
- Bleepingcomputer.com is the domain name.
- www is the hostname
- www.bleepingcomputer.com is the hostname as well!!!
Conclusion
As you can see hostnames can lead to a bit of confusion, but once you understand
them, which you should now, you should not have much trouble using these terms.
I hope you found this tutorial informative, and you would like to discuss this
forum please do so in the tutorials section of the forums.
--
Lawrence Abrams
Bleeping Computer Basic Internet Concepts Series
http://www.bleepingcomputer.com
Source of Original Content, Tutorials, Help and Computer Basics for the beginning or novice computer user.