Domain Name System

The Domain Name System (DNS) is the phonebook of the Internet. Humans access information online through domain names, like nytimes.com or espn.com. Web browsers interact through Internet Protocol (IP) addresses. DNS translates domain names to IP addresses so browsers can load Internet resources.


Each device connected to the Internet has a unique IP address which other machines use to find the device. DNS servers eliminate the need for humans to memorize IP addresses such as 192.168.1.1 (in IPv4), or more complex newer alphanumeric IP addresses such as 2400:cb00:2048:1::c629:d7a2 (in IPv6).


How DNS work?


To understand how domain names actually work, we will take a look at what happens when you enter it in your browser.

When you enter a domain name in your web browser, it first sends a request to a global network of servers that form the Domain Name System (DNS).

These servers then look up for the name servers associated with the domain and forward the request to those name servers.

For example, if your website is hosted on Bluehost, then its name server information will be like this:

ns1.bluehost.com
ns2.bluehost.com

These name servers are computers managed by your hosting company. Your hosting company will forward your request to the computer where your website is stored.

This computer is called a web server. It has special software installed (Apache, Nginx are two popular web server software). The web server now fetches the web page and pieces of information associated with it.

Finally, it then sends this data back to the browser.

Different Types of Domain Names


Domain names are available in many different extensions. The most popular one is .com. There are many other options like .org, .net, .tv, .info, .io, and more. However we always recommend using .com domain extension.

Let’s take a more detailed look at different types of domain names available.

1. Top Level Domain – TLD

Top level domain or TLD are generic domain extensions that are listed at the highest level in the domain name system.

There are hundreds of TLDs, but the most popular ones are .com, .org, and .net. Other TLDs are lesser known and we don’t recommend using them. For example, .biz, .club, .info, .agency, and many more.

2. Country Code Top Level Domain – ccTLD

Country code top-level domain or ccTLD are country specific domain names which end with country code extension like .uk for the United Kingdom, .de for Germany, .in for India.

They are used by websites that want to target audiences in a specific country.

3. Sponsored Top Level Domain – sTLD

Sponsored top-level domain or sTLD is a category of TLDs that has a sponsor representing a specific community served by the domain extension.

For example, .edu for education-related organizations, .gov for the United States government, .mil for the United States military, and more.


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