Explain how to implement logging in a Node.js application.

Logging is essential for tracking application behavior. You can use libraries like winston or morgan for logging in Node.js applications. Example with winston:

const winston = require('winston');

const logger = winston.createLogger({
  level: 'info',
  format: winston.format.json(),
  transports: [
    new winston.transports.File({ filename: 'error.log', level: 'error' }),
    new winston.transports.Console()
  ],
});

logger.info('This is an informational message');
logger.error('This is an error message');