What is Server Propagation?
So, at this point, you have just put your DNS nameservers into your the software where you registered your domain. The DNS numbers point to the server your site will be housed on, so you have to tell the registrar where it is going. Once you have that done, You go to your browser right away and your site isn't there :(
Why is that so? As you can see in the photo above, servers sit all over the world. When you put those DNS numbers into the registrars software, that server could be half way across the world from you.
So, think about this. Each server processes its cache at random intervals then sends the information out to other servers. The servers that receive the new information, they process it into their cache and prepare for their next transmission to more servers. Depending on how far away from a server you sit, it could take quite a while for the changes on the server you made to get to the server you access the internet on.