Callbacks

Lesson in the Node.js Roadmap · Stage 6: Command Line Apps

Last updated 14 September 2026

What is Callbacks?

Node.js, being an asynchronous platform, doesn't wait around for things like file I/O to finish - Node.js uses callbacks. A callback is a function called at the completion of a given task; this prevents any blocking, and allows other code to be run in the meantime.

Study this in the interactive course See the whole Node.js roadmap

Free resources to learn Callbacks

Official docsAsynchronicity in Programming Languages
ArticleWhat are Callbacks?

Callbacks: common questions

Can I learn Callbacks in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Callbacks in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Callbacks tutorial for beginners?

It is lesson 33 of 113 in the free Node.js roadmap, in stage 6, Command Line Apps. If you are new to Node.js, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.