# Assertion Errors

An `AssertionError` in Node.js is an error that is thrown when the `assert` module determines that a given expression is not truthy. The `assert` module is a built-in Node.js module that provides a simple set of assertion tests that can be used to test the behavior of your code.

Visit the following resources to learn more:

- [@official@Node.js Assert](https://nodejs.org/api/assert.html#new-assertassertionerroroptions)