The significance of using a content delivery network (CDN) lies in its ability to enhance website performance and availability. By caching content across multiple servers worldwide, a CDN reduces latency and improves page load times for users, regardless of their geographic location. This optimization leads to better user experience and can positively impact search engine rankings. Additionally, CDNs can provide protection against DDoS attacks and ensure reliable content delivery during traffic surges, making them essential for organizations aiming for consistent and efficient online operations.