The primary function of a content delivery network (CDN) is to improve the performance, reliability, and security of content delivery over the internet. CDNs achieve this by distributing content across multiple geographically dispersed servers, minimizing the distance data must travel to reach users. This results in faster loading times and reduces latency for users accessing websites and applications. Additionally, CDNs help mitigate traffic spikes and protect against various cybersecurity threats, ensuring a smooth experience for end-users.