What Is Routing and How Do Route Methods Work in Express?

Now that you've built a basic Express app, it's time to take a closer look at routing and how it works. In Express, routing is how you define the endpoints of a web application. You can think of routes as rules that tell the app how to respond when a user visits a specific URL. Let's look at our simple Express app again: ```javascript const express = require("express"); const app = express(); const port = 3000; app.get("/", (req, res) => { res.send("Hello World!"); }); app.listen(port, () => { console.log(`Example app listening on port ${port}`); }); ``` In this example, the app defines a route for the root URL (`/`). When a client sends a GET request to this path, the server responds with the text `Hello World!`. The app then starts listening for incoming requests on port `3000`. But there are other route methods. Express lets you handle different types of HTTP requests by using different routing methods. The most common ones are: * `app.get()` – retrieves data * `app.post()` – creates new data * `app.put()` – updates existing data * `app.delete()` – deletes data Each method defines how your application should respond to a specific HTTP request at a specific route. Here are a few simple examples: ```javascript app.post("/submit", (req, res) => { res.send("Form submitted!"); }); app.put("/update", (req, res) => { res.send("Item updated!"); }); app.delete("/delete", (req, res) => { res.send("Item deleted!"); }); ``` In each case, Express listens for a request with a particular HTTP method and URL path, then runs the corresponding handler function to send a response back to the client. You can test these routes using tools like Postman or `curl`, which let you send different types of HTTP requests to your server. And that’s routing in Express - it’s simply about defining how your application responds to different requests.