What does Subdomain mean?
A subdomain is a domain that is a part of a larger domain under the Domain Name System (DNS) hierarchy. It is used as an easy way to create a more memorable Web address for specific or unique content with a website. For example, it could make it easier for users to remember and navigate to the picture gallery of a site by placing it in the address gallery.mysite.com, as opposed to mysite.com/media/gallery. In this case, the subdomain is gallery.mysite, whereas the main domain is mysite.com.
A subdomain is also known as a child domain.
Techopedia explains Subdomain
A subdomain is basically a child domain under a larger parent domain name. In the larger scheme of the Domain Name System, it is considered a third-level domain used to organize site content. In the Web address example above (gallery.mysite.com), the suffix ".com" is the first-level domain, "mysite" is the second-level domain and "gallery" is the third-level domain.
Uses of subdomains include:
- Organizing website content according to category, i.e., gallery.mysite.com, faq.mysite.com and store.mysite.com
- Sharing the allotted domain space with other users by providing them subdomains and their own username and password with varying levels of feature access. For example, admin.mysite.com, user1.mysite.com and guest.mysite.com
- Shortening long links and making them easy to remember. For example, the link "http://mysite.com/offers/bonus/referal_id^56$#9?.asp" can be placed into the subdomain "referral.mysite.com" to make it easier to navigate and remember.