A domain name is used to identify a website. Businesses commonly have a domain name that is their name with the ".com" domain suffix after it. For example, the domain name of Microsoft's primary website is "microsoft.com." Some web-based businesses and organizations even name their brands after their domain name. For example, both the name and domain name of this website is "PC.net."
When you access a website in a web browser, the domain name is actually translated to a specific number called an IP address. This translation is performed by a system called DNS, which directs your browser to the appropriate location.
While all websites have a domain name, not all registered domain names have a corresponding website. For example, cybersquatters may register multiple domain names they intend to sell or use in the future. Until the website is published, the domain name will not be accessible on the Web.
If you want to register own domain name, you can get one through a registrar like GoDaddy.