Understanding CDNs (Content Delivery Networks)

I said I'd be writing about concepts I've frequently come across but never really stopped to properly understand. Today it's CDNs(Content Delivery Networks) This one is interesting because it's not just something I've seen in everyday SPAs. I keep running it across tools and services I actually work with, and at some point I had to sit down and figure out what exactly is going on here. So what is even a CDN? At a high level, it's a system that makes sure your content gets to users faster, no matter where in the world they're requesting from. Here's the version I had in my head before digging in: It has something to do with caching. Data is being served from the edge of a network. Some technologies take advantage of CDNs to deliver their content faster That's... not wrong. But it was pretty vague. Let me break it down properly. The problem CDNs Solve Let's say you deploy a web app and your server is sitting somewhere in the United States, Frankfurt, or wherever Vercel spins things up. N