DNS is the most critical infrastructure, that's publicly available for use to everybody out there. You can infact say that, its a single point of failure, that can take down the world wide web.
I have tried to explain the working of DNS in one of my post. However, its impossible to conclude the entire topic, in one or even multiple posts for that matter. So i will be posting, different topics related to DNS, separately for giving a better understanding to the reader.
Read:How Does DNS Work
