What is Middleware in Express and How It Works Every Express beginner eventually reaches this moment: You open some backend project and suddenly see this mysterious thing everywhere: ```js id="a72ks1" app.use() Then somebody says: > “Oh that’s middleware.” And beginners immediately pretend they understood. Meanwhile internally: > “What even is this creature?” Because middleware sounds complicated. But the reality is surprisingly simple. Middleware is basically: > a checkpoint system between request and response. That’s it. In this article, we will understand: * what middleware actually is * where it sits in Express * how request flow works * execution order * role of `next()` * types of middleware * real-world examples like: * logging * authentication * validation And no, we are not diving into Express internals deep enough to summon ancient backend demons.…