There are tens of millions of hosts on the internet. An IP address is allocated to each host to distinguish them from one another. However, an IP address doesn't have any actual meaning to it, which makes it hard to remember, and this is why domain names come into play.

A domain name, comprised of letters, digits, -, ., and other symbols, is an easy-to-remember server address (such as website, email, and FTP) designed for better communication.

A domain name corresponds to an IP. A specialized domain name system (DNS) server on the internet is used to translate between domain names and IPs. When you enter a domain name in your browser, DNS will translate it into an IP to locate the appropriate server and open the requested page.

If you want to set up a server to publish information on the internet, you need to register a domain name first, which is a basic for establishing services on the internet. Since domain names are registered on a "first-come, first-served" basis and every registered domain name must be unique on the internet, you are advised to register your domain names as soon as possible.