# CommonJS

CommonJS modules are the original way to package JavaScript code for Node.js. Node.js also supports the ESModules standard used by browsers and other JavaScript run-times, but CJS is still widely used in backend Node.js applications. Sometimes these modules will be written with a .cjs extension.

Visit the following resources to learn more:

- [@article@How the CJS Module System Works](https://blog.risingstack.com/node-js-at-scale-module-system-commonjs-require/)
- [@video@How to Import and Export Modules in CJS](https://www.youtube.com/watch?v=XTND4rjATXA)