A CDN, or Content Delivery Network, is a system of distributed servers (network) that deliver webpages and other Web content to a user based on the geographic locations of the user, the origin of the webpage, and a content delivery server.
This service is effective in speeding up the delivery of content of websites with high traffic and websites that have global reach. The closer the CDN server is to the user geographically, the faster the content will be delivered. CDNs also protect from large surges in traffic.
CDNs serve a large portion of the Internet content today, including web objects (text, graphics, and scripts), downloadable objects (media files, software, documents), applications (e-commerce, portals), live streaming media, on-demand streaming media, and social networks.