```js
const express = require('express');
const app = express();
// app object has a few methods:
// HTTP verbs/REST verbs
//CRUD correspondence
// 1. GET (read)
// 2. POST (create)
// 3. PUT (update)
// 4. DELETE (delete)
// 5. all - accepts any http method
// Express route methods take 2 args:
// 1. path
// 2. callback to run if HTTP request matches the specified http verb
// app.all('/', (req, res) => {
// res.send('<h1>Welcome to the homepage!');
// }):
app.get('/', (req, res) => {
res.send('<h1>Welcome to the GET homepage!');
}):
app.post('/', (req, res) => {
res.send('<h1>Welcome to the POST homepage!');
});
app.delete('/', (req, res) => {
}):
app.post('/', (req, res) => {
}):
app.listen(3000, () => {
console.log('App running on port: 3000.');
});
```