A Content Delivery Network or Content Distribution Network (CDN) is a large network of servers, which delivers content from website to end-user based on the user’s geographic location

The goal of a CDN is to serve content to end-users with high availability and high performance. As such, it uses geographical proximity as a criterion for delivering Web content.

This diagram shows the difference in set-up between a single-server distribution versus a CDN

SINGLE-SERVER DISTRIBUTION VS CDN