A content delivery network (CDN) is a technology that distributes web content across multiple servers in different geographic locations to improve user experience11. A CDN can be used to deploy web applications and files globally, so that users can access them faster and more reliably from their nearest server12. A CDN also reduces bandwidth consumption and network congestion by caching static content at the edge servers13.
Reference:
What is a content delivery network (CDN)?, IBM
Where to A/B Test: Front-End vs Back-End vs CDN vs API, Medium
Content Delivery Networks (CDNs), MDN Web Docs