Blob storage & CDNs

Your app lets users upload profile photos, and the quick instinct is to store the image right in your database next to the user's row. It works with ten users. At scale, it quietly wrecks your database: big binary files bloat it, slow it down, and make it expensive to run and back up. Files and databases are a bad match.

The standard answer has two parts. Files (images, videos, documents, anything large and binary) go into object storage, a service built specifically to hold huge numbers of files cheaply. And to serve them fast to users everywhere, you put a CDN in front, which keeps copies close to users geographically.

This unit ties together pieces you already know (the request path, the CDN, the database) into the pattern every media-heavy system uses: metadata in the database, the file in blob storage, delivery via a CDN.