Why use multiple domain names?

It's quite common for a site to be referenced by more than one
domain name. In fact, most sites are referenced by at least two:
a www version and a non-www version. These are usually set up to
reference the index page on a site and produce the same results
for a searcher.

It could, however, be argued that these are these same domain
names. So the question remains: why would someone want to have
more than one unique domain name for a single site?

Search engines - First, let's take a brief look at search
engines. In the past, it was a very common spamming technique
to purchase dozens, hundreds or in some really gross cases,
thousands of domain names, all referencing exactly the same
site. These were all submitted to the search engines, and many
of them were indexed and blindly added to the results. This is
how many questionable sites used to get top search results very
quickly and inexpensively.

The search engines have apparently caught onto this technique.
At the very least, it has become common knowledge that this kind
of spamming is not tolerated (sometimes common knowledge can be
just as effective a deterrent as actual enforcement). I know
that in the past it was normal to find many sites of different
domain names but identical content in search engine results;
today it's far more rare.

In fact, the top search engine, Google, bases it's ranking
scheme on quality of links. What this translates to is you must
get popular (higher ranking) sites to link to your site to
raise your ranking. Thus, it's a better strategy to get as
many links to a SINGLE domain name than to many different
domain names.

With this in mind, it's now considered best by most search
engine optimization specialists (at least those that know what
they are doing) to only list a single domain with the search
engines, perhaps with the www and non-www version but nothing
else.

Multiple entry points - One technique that I use on my own site
with great success is to have multiple entry points, each it's
own domain name. Let's consider a mythical site in order to
illustrate how this works.

The site is about homemaking, and thus the main domain is
"homemaking.com". Underneath this are sections about sewing,
housecleaning and cooking. You might use "homemaking.com" for
link exchanges and search engine submissions, then create three
additional domains: "sewing.com", "housecleaning.com" and
"cooking.com" (although if you actually managed to purchase
those domain names you could resell them for quite a chunk of
change).

Each of these domains would use a 301 redirect (this informs
any search engine that the page has permanently moved to a new
location) to a specific page on the site.

Those three domains would then be used in different themed
marketing campaigns. You might submit an article to a cooking
site, for instance, which referencing cooking.com. For a
newsletter about cleaning, you would use housecleaning.com. Each
domain name is merely a shortcut to the master domain, but it is
much more targeted than "homemaking.com".

Protection - If you own a business, it's a great idea to think
of some of the derivations of your site name and purchase those
as well. Thus, if you had a company named "xyz", you might also
purchase "xyzsucks" and "ihatexyz" as well. You may as well
direct these to your site, but be sure to include 301 redirects,
as you definitely do not want them in search engine indices.

Typos - Sometimes people misspell things, and domain names are
no exception. Knowing this, you can get some respectable
traffic by purchasing common misspellings for your domain name.
Just remember to use the 301 redirect method so these
misspellings are not listed in the search engines.

Other TLD's (Top Level Domains) - If possible, it's a good idea
to get the .com, .net and .org version of your domain at a
minimum. I tend to get the .us (or whatever country is
appropriate), .info and .biz versions as well. This ensures that
no matter what people type they will get to your domain. Of
course, remember to 301 redirect these domains so they don't get
listed.

For branding purposes, it's essential to get the other TLD's if
you can. If you don't you may be embarrassed to find some
pornographic or casino site has purchased your name with a
different TLD. The white house site (whitehouse.gov) is a
classic example: the .com version has nothing to do with the
white house (if you type this URL, be sure your kids are not
present).

Other TLD's with different content - In a slight alteration of
the above method, I have purchased the additional TLD's, but
made each one slightly different. To use the above housecleaning
example, housecleaning.com might be a page about housecleaning
in general, housecleaning.us might index articles specific to
the United States, and housecleaning.biz may include
information related to housecleaning businesses. Each of these
is just a page or two, and links back to the main
housecleaning.com domain.

If you use this method, be sure it's honest and sincere. Do NOT
do this to spam search engines (in fact, to be perfectly safe,
set your metatags to stop robots from indexing those pages).
These are not intended for search engines - these pages are
intended for focused marketing campaigns.

Regional content - If your site has regional content, you might
purchase specific domain names to focus on that content. For
example, if you had a stamp collection site, you could purchase
"my-stamps.to" for Tonga related stamps, "my-stamps.us" for
United States stamps and so on. You could also keep it simpler
and purchase "my-tonga-stamps.com" for your general site,
"my-english-stamps.com" for your English stamps and so on. These
should also use 301 redirects to keep the specific domain names
from being indexed.

Uses for the .NAME TLD - You might even consider purchase the
.name TLD for your senior managers. Put up simple web sites
about them, with links to your main site. These SHOULD be
indexed in the search engines, as you want people to find them
if they are looking for information about your personnel.

Don't forget email - Remember you can get email on each and
every one of the domains that your purchase. In fact, this is a
great reason to purchase additional domain names - people can
send you email by different means. So be sure to set up the
email for each and every domain to go to a general, "catch-all"
account. It's a good idea, though, to heavily spam-filter this
account as it can collect a huge amount of junk.

Subdomains - This is a great way to get much of the benefit of
the above listed techniques without purchasing additional
domain names. It does require a little more control of your DNS
entries, however, as most ISPs and web hosts will not be
willing to do these kinds of things for you.

In this case, you could define "housekeeping.com" as the
primary domain, then "cleaning.housekeeping.com",
"sewing.housekeeping.com" and "cooking.housekeeping.com" as the
subdomains. You should continue to use 301 redirects to keep the
search engines from indexing these pages.

Renewals - Don't forget to renew all of these domains each year.
At least examine each one when renewal time comes and
consciously decide whether or not you need the domain. Don't
let them expire without your knowledge. Someone else may then
benefit from your hard work.

Other people's mistakes - Sometimes you might find that the
domain you want is not available. In this case, take a look at
the WHOIS record and see when it expires. Set up a reminder for
30 days from this date and every week or so thereafter. On
those days, try and purchase the domain. Quite often,
(especially these days) you may be surprised to find the domain
has become available.

Other TLD systems - Companies such as new.net are offering many
more pseudo-TLDs such as .SHOP and .XXX to the general public. I
would avoid these new systems like the plague. These are at best
bad ideas and at worst scams. They are attempts to supercede the
official internet standard TLD system by companies with
questionable motivations. They all require browser plug-ins or
other customizations to work, and some of them come piggy-backed
with spyware and other malicious applications.

These alternate TLDs do not get indexed in search engines, and
they may conflict with future TLDs added in the official domain
name structure (and thus become useless). On top of that, they
are extremely expensive.

In my opinion, it is critical that the internet domain name
structure remain under the control of a central governing body.
While this body (currently ICANN) is not operating as desired by
the majority, it's still much better being under one umbrella
than splintering this all over the place.

Straight TCP/IP address - I am always surprised to come across
a site which is listed in search engines, ezines and other
promotions as a straight TCP/IP address. This is not only tacky
and a sign of a spammer, it's not very intelligent as well. If
you do this and move your site (changing it's IP), you will lose
all of the traffic that you have so painfully gained.

Conclusions - The point is that owning more than one domain has
many uses, although it is no longer of much value from a search
engine optimization viewpoint. Instead, you can use the other
domain names to fulfill other types of marketing and to attract
people from specific markets to your site.