What Is a Subdomain
A subdomain it is an additional part of the main domain. It is created to facilitate in organizing and navigating through the different sections of the main website.  Within the main domain one can create multiple of those.
Difference Between Domain and Subdomain
A domain name can exist without a subdomain while a subdomain cannot be in existence without a domain name. Therefore Multiple subdomains can exist on a single domain.
USES Of a Subdomain
- Testing of a new website
Most developers create subdomains so as to use for testing a website, before launching the website. Before the publishing of a website , one can use it to restructure the plugins, layout and updating of the design.
- Organization of different parts of website
It is useful in the organizing of a website without causing any damage to the website.
- Creating a different platform on the initial website.
Subdomains facilitate publishing of website content which is alternate and in the process it does not cause confusion to the targeted audience.
- Facilitates creation of multilingual website.
It enables users to be to create his or her own multilingual website. When one has various versions of his or her own website he /she is able to reach a broader audience and match the needs and the preference of the audience.
·        Creating blogs for a specified group of audiences
A user can be able to target a specific group of audience. User can be able to make blogs for different audience that suites the preference of each group.
·       Improves Search Engine Optimization
It improves the trafficking and site ranking. They are identified by search Engines as different web addresses from the main domain. Users can use their subdomains on getting new traffic and sending them to their root website. Thus improves Search Engine optimization.