and if we can go to Settings->General, and change from one format to another
Generally you can, if your server is set to know that domain.com and http://www.domain.com are them same (most are).
As for why… shorter is better 🙂 There’s nothing SEO wise that says one is better, though, it’s just what you like. Pick one, stick with it.
I think there’s no much PROS and CONS. I prefer using without the WWW just because it’s shorter and easier to write.
One way to do that is modifying the .htaccess file.
I’ll copy/paste this code from html5boilerplate, just take a look:
# ----------------------------------------------------------------------
# Suppress or force the "www." at the beginning of URLs
# ----------------------------------------------------------------------
# The same content should never be available under two different URLs - especially not with and
# without "www." at the beginning, since this can cause SEO problems (duplicate content).
# That's why you should choose one of the alternatives and redirect the other one.
# By default option 1 (no "www.") is activated. Remember: Shorter URLs are sexier.
# no-www.org/faq.php?q=class_b
# If you rather want to use option 2, just comment out all option 1 lines
# and uncomment option 2.
# IMPORTANT: NEVER USE BOTH RULES AT THE SAME TIME!
# ----------------------------------------------------------------------
# Option 1:
# Rewrite "www.domain.com -> domain.com"
<IfModule mod_rewrite.c>
RewriteCond %{HTTPS} !=on
RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]
</IfModule>
# ----------------------------------------------------------------------
# Option 2:
# To rewrite "domain.com -> www.domain.com" uncomment the following lines.
# Be aware that the following rule might not be a good idea if you
# use "real" subdomains for certain parts of your website.
# <IfModule mod_rewrite.c>
# RewriteCond %{HTTPS} !=on
# RewriteCond %{HTTP_HOST} !^www\..+$ [NC]
# RewriteCond %{HTTP_HOST} (.+)$ [NC]
# RewriteRule ^(.*)$ http://www.%1/$1 [R=301,L]
# </IfModule>
It used to be handy for Twitter to use a shorter URL, because Twitter used to post URLs and only display the first X number of characters, so people would copy and paste them and end up with a broken address.
However, Twitter has changed the way it handles URLs recently so that this is less of an issue.
If you tell people a URL without a www in it, a lot of them will put it in anyway, so I would make sure that both work!
@cycas, I’m using just site.com, but yes, I’ve made sure both www. and plain site.com work just fine.
Thanks for the info!