Hi Pratap,
This is a list of the DNS root servers:
https://www.iana.org/domains/root/servers
The root servers answer requests for the root zone which contains all top-level domains (TLD) like .com, .net, etc.
You can take a closer look at each of these here:
Here is an example (without caching):
- From your computer, you do a lookup for networklessons.com.
- Your computer forwards the request to the ISP DNS server.
- If the ISP DNS server doesn’t have an answer, it queries one of the root servers to ask which DNS servers are responsible for the .com TLD.
- The ISP DNS server sends a request to the .com TLD name server.
- The .com TLD name server answers which authoritative server is responsible for the networklessons.com domain name.
- The ISP DNS server now asks the authoritative server for the IP address of networklessons.com and gets the IP address.
- The ISP DNS answers your computer with the IP address.
As you can see, these root servers are important. Hope this helps!
Rene