Information at your fingertips, instantaneously. The days of using outdated methods for research are over now that the world has gone digital. DNS servers are one of the internet’s magic tricks that make it possible for you to access content on any device without having to worry about memorizing IP addresses or spending hours trying to find the right version of a document. But what really is a DNS server.

What is a DNS server?

DNS stands for Domain Name System. It keeps track of your computer or mobile device’s location on the internet at all times. It converts a string of characters – such as Google – into a set of numbers and letters known as an IP address. For example, a Google server would have an IP address like 213.46.131.2 . DNS servers know how to convert that string of numbers and letters into your computer’s or mobile device’s location on the internet, literally saving you from having to remember what number is for what website.

How does DNS work?

DNS servers are computers that have lists of websites, their IP addresses, and other information. Even though there are millions of computers all over the world running DNS servers, each person’s list of websites is unique to them. Your computer or mobile device logs onto a DNS server in order to find out which IP address it should use for a given website. It is important to note that any time you enter a URL into your browser or any other application, your computer or mobile device is using a DNS server to translate the URL into an IP address so it knows where to go.

For example: you type www.google.com into your browser and it tells your computer to connect to the DNS server at 192.3.65.10 . Here’s how this might look in your internet browser:

You can see that when you go to a website, the IP address is the first thing you see (in this case, 213.46.131.2 ). The IP address is actually made up of 4 numbers separated by periods (in this case, 213-46-131-2). When you type a URL into any application or try to access an online resource, your computer or mobile device looks up the website’s IP address on a DNS server. DNS servers often keep the IP address of the original website and another that you use to access the resource.

From there, your computer or mobile device sends a message to the chosen DNS server and then receives a reply in return, telling it exactly how to connect to the website.

Today, most people access websites without even thinking about DNS servers. This is because it’s almost impossible to browse the internet without using them. However, it’s important to know that DNS servers are just one of many ways that allow you to access the internet. There are also IP addresses, subnetting, IP routing/forwarding, and various other computer science functions that allow your computer or mobile device to connect to the internet.

What is the difference between a DNS server and an ISP?

DNS servers are used by all computers and mobile devices on the internet so there’s nothing special about them. However, your ISP is different than a DNS server because an ISP provides your communications channels (usually through cables/wireless etc. which are the means through which you access the internet). So in short, they are both essential for your computer or mobile device to access the internet, but they are two different things.

For example: your ISP is Comcast, and DNS servers are Google DNS1, Google DNS2, etc. Comcast connects you to the internet using cables/wireless signals that give you access to the Google DNS servers. If any of them are down or inaccessible for some reason then you won’t be able to get on the internet. A common error message that you might see is “DNS server not responding” or “DNS lookup failed” (you may need to contact your ISP if this happens).

What is a Resolver?

A resolver is a computer that handles the translation of information from one system (such as an IP address) to another (such as a website). A resolver converts an IP address into the domain name of the resource it refers to. Usually, this DNS server will be hosted on your ISP. For example: if you were trying to find a website and you entered an incorrect URL into your browser, your computer would contact your ISP’s DNS server and ask what website it should display.

What is a Reverse DNS Lookup?

A reverse DNS lookup is when you enter a fully qualified domain name into a DNS resolver and the DNS server returns the corresponding IP address. For example, if you wanted to find out what IP address www.google.com was using, you would enter the following information into your computer’s browser:

You can see here that “www” is actually “74.125.196.100” and “google” is actually 74.125.199.35 . When you enter the domain name into the DNS server, it will return an IP address.

Conclusion

Now that you know what a DNS server is and how it works, you can easily go back to using the internet without having to worry about knowing which IP address is for what website. It’s enough of a hassle to have to memorize the thousands of websites that exist today, without having to remember an unlimited number of IP addresses.

Read an article on why you need VPN here.