A content delivery network (CDN) is a system of distributed servers that work together to deliver web content to users more efficiently. By storing copies of content, such as images, videos, and web pages, in multiple locations around the world, CDNs reduce the distance data must travel. This helps improve loading times and enhances the overall user experience. CDNs also provide benefits like increased reliability and security. If one server goes down, others can take over, ensuring that users can still access the content. Additionally, CDNs can help protect against DDoS attacks by distributing traffic across multiple servers, making it harder for attackers to overwhelm a single point.