A subdomain is a web address, that is under a main, or a root domain name. An illustration is something.domain.com, in which domain.com is the main domain address, while "something" is the subdomain below it. Each and every subdomain can have its own website and records i.e. aside from employing the domain name as a part of the whole web address, a subdomain can be totally independent and also hosted by a different company. Using a subdomain can be very beneficial if you wish to have different web sites which are associated in some way. For instance, you can have an on-line store under the main domain plus a forum under a subdomain in order to provide means for your customers to ask questions and share views concerning your products. The main advantage of employing a subdomain as opposed to a subfolder is that the sites are going to be separated, so you're able to update one of them or perform maintenance not affecting the other.