Do some reading on domain names and what good ones are, as well as a little bit on search engine optimization and eventually you will come across the very sound advice to only use www.domain.com or domain.com, but not both.
The idea is two-fold. First, you don’t want to lose out on your search engine rankings by having people (and yourself) point to both www.arcticllama.com AND arcticllama.com, because the search engines consider these to be different pages. Second, you don’t want to confuse visitors who might wonder what the “real” address is, even though it doesn’t really matter.
What you won’t find is advice on which one is the better choice. Most sites will just say, choose whichever one you like and go with it. Well, I’ve found that there is a best practices for choosing whether or not to use www in your domain name.
Don’t use WWW in your domain name. Why?
As the Internet evolves, things are always changing. One change underway right now is the emergence of mobile-based or mobile versions of websites. While there is no standard practice yet, many sites are choosing to use an “m” and then the domain name, like m.arcticllama.com for their mobile sites. (I don’t have one yet.)
If you are using www, like I am, you are boxed out of doing this. We never know what the future will bring, but there might be all manner of single letter prefixes for various things, or other evolutions. Either way, the www will only hamper you, while the no www provides full flexibility.
Unfortunately, I did all of my recent sites with www, so I’ll be working over the next months to eliminate that without causing any harm to my site’s traffic.
Save yourself the trouble, and use your domain name without the www and then set up your site so that any visitors to www.domain.com get redirected to domain.com. You’ll thank me later.