Where do files go after you upload them, and how do you get them back? You've set up Multer. You've sent a POST request with an image. The server didn't crash, and you got a success response. But... where did the file actually go? And more importantly, how do you show that uploaded profile picture on your frontend? When I first learned file uploads in the ChaiCode Web Dev Cohort 2026, I thought the hard part was receiving the file. It turned out the trickiest part was figuring out how to store it securely and serve it back to the client. If you don't handle this correctly, your server's hard drive will fill up with junk, your URLs will break, or worse — you'll expose a massive security vulnerability. Let's break down exactly how to store and serve files in Express. Where Are Uploaded Files Stored? When a user uploads a file, the server has to put the binary data somewhere. You essentially have two options: Local Storage or External Storage .…