The Websites section allows you to add/remove master websites, alias sites and sub-domain sites, for all domains listed under your account.
Master Sites are websites that are the “main” site for a domain (foo.com and www.foo.com). These sites get setup with directories directly under your web space, and web stats are available for these sites.
Alias Sites are like e-mail aliases, in that any requests for the alias domain or www.aliasdomain, will be redirected to the “destination” site. For example, if you had a .com website (say, www.foo.com), and you also owned the .ca version of the domain (foo.ca), you could make www.foo.ca an alias to www.foo.com, and then both domains would go to the same site (and the same content).
Alias Web sites can only be aliased to Master Sites listed under your account, and hosted by Mr.Host. Since alias sites point to Master Sites, they don’t have their own directories, content or web stats.
Sub-Domain sites, are sites based off of a Master Site. For example, you could create the sub-domain site “forums.foo.com”, for you web-based forums. Your sub-domain portion (forums) can be anything you want, other than “www”, but can only contain letters (a-z), numbers (0-9) and dashes (-), and can only be up to 50 characters long.
Sub-Domain Sites will have a directory, under their master site, created for their content. So, if you create the sub-domain site “forums.foo.com”, the directory “www.foo.com/forums/” will be created for it’s content.
Sub-Domain sites can ONLY be created for valid, active Master Sites, but they do have web stats available, separate from their master site.