A domain name, in simple terms, is the “address” of a website. Using a domain name is primarily to make it easier for humans to find information online. Domain names make it easy for web servers that host websites to connect to the computers of visitors browsing the internet.
In more technical terms, domain names describe, using a string of letters, numbers, or symbols, an Internet Protocol (IP) Address. The primary function of a domain name is to be a human interpretable stand-in for an IP Address.
So, what is an IP address? An IP address is the numeric address of any domain on the internet. IP addresses consist of 4 groups of up to 3 numbers between 1 and 255 and separated by periods, such as: “18.104.22.168”. Similar to the way that a proper name is listed in the phone book next to a phone number, domain names relate an alphanumeric string to this numeric address. These numbers are not random, they are structured, similar to the reference numbers are applied to categorize the books in a library. Just as library codes help to identify the title of a book, the IP addresses structure contains information pertaining to the geolocation of the host computer.
The primary intention for creating the system of IP address is for each computer to have a unique identifier. The main reason for creating domain names is so that the people that connect to that network of computers have an easy to remember word or phrase to type in to get connected, rather than needing to remember a string of numbers.
With the because of the way the IP address and domain name system works, you have the freedom to type either the domain name or the IP address into a web browser and you will be directed to the same page. This is because Internet Service Providers maintain a list of IP address to domain name tables in order to match the domain name to the appropriate website server. This type of matching database is held on what is called a Domain Name Server (DNS).