With www vs Without www -When to use them to their domain.

I don't think it is so much that others do not use it in their domain name as it is simply the understood part of a domain name/URL/address. I didn't have a choice whether or not to add it when I set up my websites. It is sort of standard, so standard actually, that you no longer have to type it for the brower to find the site for you.

It is very rare to find a site that doesn't accept both options - i.e. with or without www. You don't need to type it every time. The www part is routinely setup as an alias in most web servers. If you ever go off the www part of the Internet, (and it is quite possible) then you are probably lost!

Most internet browsers today have the capability of locating and opening a website even if you didn't type in there www prefix. So, for most people today, because they want to save time typing the prefix in the browser bar, they just type in there domain name right away, and when they hit enter, same results!