CDN stands for a content delivery network, which is a geographically distributed group of servers that work together to provide fast Internet content delivery.
A CDN allows to quickly transfer the assets needed for loading Internet content, including HTML pages, javascript files, stylesheets, images, and videos. A CDN significantly improves loading times for pre-lands and landing pages, resulting in better traffic delivery and conversion rates.
Another advantage of a CDN is increasing content availability and redundancy that operate as a load balancing and a failover service. It provides better service availability and better protection in case of DDOS or other service attacks.