A content delivery network (CDN) refers to a geographically distributed group
of servers which work together to provide fast delivery of Internet content.

A CDN allows for the quick transfer of assets needed for loading Internet
content including HTML pages, javascript files, stylesheets, images, and videos.

The popularity of CDN services continues to grow, and today the majority of web
traffic is served through CDNs, including traffic from major sites like 
Facebook, Netflix, and Amazon.