Content Delivery Networks (CDNs) enhance website performance, reduce latency, and improve security by using globally distributed servers. Factors to consider when choosing a CDN provider include performance, security features, pricing structure, ease of integration, customer support, and scalability. Popular CDN providers each have unique advantages, such as Cloudflare for strong security and affordable options, Akamai for enterprise-grade performance, Amazon CloudFront for AWS integration, Fastly for real-time caching, and BunnyCDN for simplicity. Testing a CDN through performance benchmarking, trial periods, and support evaluation is recommended before any long-term commitment to ensure it meets your business needs.