What is the difference between using module.exports and the exports property in Node.js when exporting modules?

In Node.js, module.exports and exports are related to module exports but work slightly differently.

• module.exports is the object that is actually returned when importing a module.
• exports is simply a reference to module.exports by default.

If you assign a new value to exports, the connection to module.exports is lost, and the export will not work as expected.

Example of correct usage:

// Adding properties to exports
exports.foo = function() { return 'foo'; };

// Or replacing the entire export
module.exports = function() { return 'bar'; };

If you write it like this, the export will not work:

exports = function() { return 'bar'; }; // INCORRECT

Because exports now points to a new function, but module.exports remains the same object that is exported.