A subdomain is a web address, that's under a main, or a root domain name. An illustration is something.domain.com, where domain.com is the main domain name, while "something" is the subdomain below it. Every single subdomain can have its own site and records i.e. apart 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. Employing a subdomain can be quite practical if you wish to have different web sites that are related in some way. For example, you may have a web-based store under the main domain plus a forum under a subdomain in order to supply means for your clients to ask questions and share views about your products. The benefit of using a subdomain as opposed to a subfolder is that the websites will be separated, so you're able to update one of them or perform maintenance not affecting the other.