It is not always necessary to register a new domain name when the one you already own will work perfectly fine. Rather than registering a new domain name, you can always create a subdomain using a domain you already own.
A subdomain is a second website, with its own unique content, but there is no new domain name. Instead, you use an existing domain name and create a subdomain by adding a prefix to the domain, e.g. domain: domain.com, subdomain: sub.domain.com. Any prefix creates a subdomain. With Servage you can create as many subdomains as you like.