How can you connect to a MongoDB database using Node.js?

You can use the mongoose library to connect to a MongoDB database easily. First, install it using npm, then use the following code:

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/mydatabase', { useNewUrlParser: true, useUnifiedTopology: true })
  .then(() => console.log('MongoDB connected'))
  .catch(err => console.error('MongoDB connection error:', err));