Subdomains are addresses like subdomain.domain.com. The subdomain can either act as if it were an entirely different site, not part of your primary domain (using the Add‑on Domains feature discussed in Chapter 10) or it can serve as a shortcut to redirect you to another place either in your site or to anywhere on the Internet.

To create a subdomain, just type the subdomain you want into the field next to your domain name, then select the domain name you want the subdomain to be a part of and click Add. It is interesting to note that you can select subdomains that you have already created from this list. Therefore, it is possible that if you created a subdomain my at domain.com, you could subsequently create a subdomain is at my.domain.com ending up with is.my.domain.com and then finally adding this to come up with this.is.my.domain.com.

All subdomains default to loading the index page in a similarly named directory. For example, if you create the subdomain, gallery.domain.com,...