CDN stands for Content Delivery Network. It is a network of distributed servers located at various geographical locations around the world. The primary purpose of a CDN is to deliver web content, such as images, videos, CSS, JavaScript files, and other static assets, to end-users more efficiently and quickly. CDNs can significantly speed up websites and improve user experience by employing several key mechanisms:

1. Caching: When a CDN is configured for a website, it caches static content on its servers. When a user requests a page, the CDN delivers the cached content from the server closest to the user’s geographical location. Caching reduces the load on the origin server, resulting in faster page load times.
2. Reduced Latency: By distributing servers across various locations, CDNs bring the content physically closer to users. Reduced physical distance means lower latency and faster data transfer times, as data doesn’t need to travel as far to reach the user’s device.
3. Load Balancing: CDNs are equipped with load balancing capabilities. When multiple servers handle user requests, the load is evenly distributed, preventing any single server from becoming overwhelmed and ensuring faster response times.
4. Global Scalability: CDNs are designed to scale globally and handle traffic spikes efficiently. They can handle a large number of simultaneous requests from users all over the world without affecting website performance.
5. DDoS Protection: Many CDNs offer protection against Distributed Denial of Service (DDoS) attacks. They can absorb and mitigate malicious traffic before it reaches the origin server, helping maintain website availability during an attack.
6. SSL Termination: CDNs can offload SSL/TLS encryption and decryption processes from the origin server, reducing the server’s workload and speeding up secure connections.
7. Browser Optimization: Some CDNs offer additional optimizations, such as minification, compression, and HTTP/2 support, which further improve website performance and reduce page load times.

Overall, a CDN acts as a distributed network of servers that collaboratively deliver content to users, making it an effective way to speed up websites, enhance user experience, and ensure reliable content delivery worldwide. By leveraging CDNs, website owners can provide faster load times and a smoother browsing experience, regardless of a user’s geographical location.