What does HostGator mean when they offer Shared Web Hosting for unlimited domains?
This means we allow you to host any amount of domains you want, for one low price, and no additional charge for each domain you add.
You can have different websites for each domain, and/or can point more than one domain to any of your sites.
However, you must already own the domain names you want to use.
If you do not own a domain, you typically want to register (buy) one to use with your hosting. If you want more than one domain name, you will need to register each domain before you can use it.
Domain registration is not free. Most registrars charge $10 to $20 per year for a domain name. Sometimes you can find deals for cheaper domain names, and some domain TLD's (types like .us and .co) cost more.
Advanced Tip: If you already registered one domain, you can make free names which do not need to be registered, but act like unique domains (to be used for separate websites). These are called subdomain names!