A Content Delivery Network (CDN) is a distributed network of servers used to deliver web content to users based on their geographical location. The idea behind a CDN is to improve the performance and availability of content by bringing it closer to the users who access it.
CDN servers are strategically placed in data centres around the world and cache a copy of a website's content. When a user requests a web page, the CDN directs the user to the server that is geographically closest to reduce the time it takes to download the content.
CDN also use various techniques such as load balancing and caching to ensure high availability and stability of the website