The term ‘internet content’ is very broad, and includes different types of assets: from images and videos, to HTML pages and javascript files. To be able to load all of that content in a fast, reliable, and secure way, a content delivery network, or CDN, is needed. 

It is essentially a network of servers linked together that are placed at Internet exchange points (IXPs) –key high-speed interconnected locations that set the base for the distributed nature of the CDN. This way, a CDN can handle more traffic than origin servers.

Most web traffic is served through CDNs, including Amazon and Netflix, two of the largest sites online. Despite the fact that a CDN doesn’t host content, its main role is to improve website performance as it helps cache content. 

Once the content is cached, hosting bandwidth and latency is reduced, website load times are improved, the risk of a DDoS attack is reduced, among other benefits. These make CDNs a good ally when trying to prevent service malfunctions or interruptions.