CDN is short for Content Delivery Network, which is a system of distributed servers (or networks) located all over the world that deliver web pages and other web content to users based on their geographic location, web page origin, and a content delivery server.
The CDN is useful in speeding up the delivery of content to websites with global reach and high traffic. As a browser loads static content, this request is automatically routed to a server located closest to the browser, making the content load faster and preventing the site from being overloaded, since the traffic is spread out over many servers.
