What is a DNS Server?
The simple answer is that a DNS server tells your web browser where a domain such as www.google.com leads to. That might answer some questions but not all so let's go a little more in-depth to how these DNS servers work. So to first understand a DNS server we will need to take a brief look at what a website is. A website is a group of files written in a language that web browsers understand that are sitting on a computer that is connected to the internet. To view those files that make up a website you need to access them via a web browser. Our problem starts over the fact that the web browser needs to be told where these files are because there are millions of computers connected to the internet and the web browser can't possibly know which computer these files that you want to view are on. So we just enter in the name of the computer and get on our way with browsing the internet right? Wrong, it is not as simple as that because the way that computers are named on the internet is via IP addresses. IP addresses are numbers that distinguish one computer from the rest of these computers on the internet. They usually look something like this "22.214.171.124". The next problem comes about when it becomes very hard for the average person to remember a string of numbers like that to get to a website. Could you imagine having to type in "126.96.36.199" every time you wanted to use google? Instead, we use Domain Names to distinguish these computers for us. How does the web browser know that www.google.com goes to 188.8.131.52 though? Well, that is when the special server type called a DNS server comes into play. When you type www.google.com into your web browser it asks the DNS server "Where does this domain go?" and the DNS server tells your web browser the correct IP address of the computer that has that website.
Who Run the DNS Servers?
So there are a lot of companies that run public widely used DNS servers such as Google, Sprint, OpenDNS, and CloudFlare to name a few. The DNS server that you use is based off of your settings, your location, your Internet provider, and several other factors.
Why Do I Have to Wait for
DNS Servers to Propagate?
For your web browser to get the correct answer from your DNS server your webmaster has to send a request to the DNS server to update it's information to the correct settings. Since there are many DNS servers around the world this request needs to be processed by each DNS server before they will send the correct information around the world. If you try to use a domain before the DNS servers are updated then you will likely get an error by your web browser or go to a completely different place than intended. So I am sure you are wondering how long does it take for these servers to propagate? Well that depends on a lot of different factors and a common estimate is 24-48 hours. That number is on the higher side though and more often than not we can get those updated within a couple hours, especially in the USA.