freeCodeCamp/curriculum/challenges/english/blocks/lecture-understanding-routing-in-express-js/69a848d4f1d1b4b9e176a026.md

id, title, challengeType, dashedName

id	title	challengeType	dashedName
69a848d4f1d1b4b9e176a026	What Is Routing and How Do Route Methods Work in Express?	19	what-is-routing-and-how-do-route-methods-work-in-express

--description--

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:

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:

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.

--questions--

--text--

What does app.get('/', ...) do?

--answers--

It deletes the homepage.

--feedback--

Think about what happens when a user visits /.

---

It creates a database.

--feedback--

Think about what happens when a user visits /.

---

It responds to a GET request at the root URL.

---

It shuts down the server.

--feedback--

Think about what happens when a user visits /.

--video-solution--

3

--text--

Which route method would you use to update an existing item?

--answers--

app.get()

--feedback--

Think about the method used for updates.

---

app.post()

--feedback--

Think about the method used for updates.

---

app.put()

---

app.delete()

--feedback--

Think about the method used for updates.

--video-solution--

3

--text--

What do Express route methods like app.get() or app.post() do?

--answers--

They start the server listening on a port.

--feedback--

Think about how Express knows what to do when a request is made to a certain URL.

---

They connect the app to a database.

--feedback--

Think about how Express knows what to do when a request is made to a certain URL.

---

They define how the app responds to specific HTTP requests and URLs.

---

They stop the server.

--feedback--

Think about how Express knows what to do when a request is made to a certain URL.

--video-solution--

3