How Do Domain Names Work?
A domain name (sometimes called URL) is a human readable alias for an IP address. An example of a domain name is adminhacks.com. A active domain name will point to an IP address, which looks something like 10.132.21.4. A set of numbers is a lot harder for humans to remember than a domain name. Imagine every time you wanted to access any website, instead of typing the website name you had to type in a set of numbers.
Computers use IP addresses. There are two versions of IP addresses, IPv4 and IPv6. IPv4 is a set of four numbers between 0 and 255 separated by periods; e.g. 192.168.21.9. An IPv6 address is a set of eight four digit hexadecimal numbers separated by colons; e.g. 2001:0db8:85a3:0000:0000:8a2e:0370:7334. These IP addresses work great for computers, but they are definitely not something you would want to memorize and type out every time you wanted to visit a website.
Domain names come in to the rescue. A domain name is a word or a set of words. -- something like adminhacks.com. This is is much easier to remember for human beings. But a domain name in itself is meaningless to computers. So there is this thing called The Domain Name System (DNS). DNS is like a phone book. A phone book is used to find a persons name and match it to a telephone unmbers. DNS takes a domain name and finds the corresponding IP address. So when you type in adminhacks.com into a web browser, your computer ends up translating that into the IP address of the server which hosts adminhacks.com.
Domain names get assigned through domain registrars. There are these things called top level domains. These are the .com, .net, .org and other domain name endings that you see when you access a website. These are agreed upon by nonprofit groups which help run the Internet as we know it.
There are associated servers which answer queries for top level domain names. They keep a database of where to find registered domain names. These servers then point to the domain registrars which know where to find the IP address of a full domain name.
So say you want to visit adminhacks.com for the first time ever. Your computer does not know what the IP address for the site is, but it does see that the website's URL ends in '.com'. So it finds a top level domain name server for the .com domains and it asks who has information for adminhacks.com. That top level server replies with the domain registrar for adminhacks.com. In this case it is NameSilo. NameSilo then responds with the DNS information, which provides the actual IP address of the site.
So a domain name registrar is a place that top level domain servers point to which in turn responds with where to find the DNS information. The whole process looks like this:
If a domain name is not registered to a domain registrar then there is no way for the world to know where to find the corresponding IP address. However, a website does not need a domain name. You can certainly run a website from an IP address. Without a domain name, the website will just be hard to remember and find.
Check out the top domain name registrars.