> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/getify/You-Dont-Know-JS/llms.txt
> Use this file to discover all available pages before exploring further.

# First Edition

> Access the original first edition of the You Don't Know JS book series

The original **first edition** of the You Don't Know JS book series is still available for those who want to reference it or prefer the original content.

<Card title="First Edition Repository" icon="book" href="https://github.com/getify/You-Dont-Know-JS/blob/1st-ed/README.md">
  Access the complete first edition on GitHub
</Card>

## About the First Edition

The first edition of You Don't Know JS was a groundbreaking series that helped countless developers gain a deeper understanding of JavaScript. Released over the course of several years, it covered the fundamental mechanisms of the JavaScript language in unprecedented detail.

### First Edition Books

The original series included six books:

1. **Up & Going** - An introduction to programming and JavaScript basics
2. **Scope & Closures** - Understanding JavaScript's scope and closure mechanisms
3. **this & Object Prototypes** - Deep dive into the `this` keyword and prototypal inheritance
4. **Types & Grammar** - Exploring JavaScript's built-in types and grammar
5. **Async & Performance** - Asynchronous programming patterns and performance optimization
6. **ES6 & Beyond** - New features in ES6 and future JavaScript additions

<Info>
  The first edition books are still freely available to read on GitHub, but they are no longer maintained or updated.
</Info>

## Differences Between Editions

The **second edition** represents a significant evolution of the series, with major changes in structure, content, and scope.

### What Changed

<AccordionGroup>
  <Accordion title="Updated for Modern JavaScript" icon="code">
    The second edition is completely rewritten to reflect modern JavaScript (ES6+) as the baseline, rather than treating newer features as "future additions." The content assumes readers are working with contemporary JavaScript environments.
  </Accordion>

  <Accordion title="Restructured Content" icon="sitemap">
    The second edition reorganizes topics for better learning flow:

    * **Get Started** - A more comprehensive introduction
    * **Scope & Closures** - Completely rewritten and expanded
    * **Objects & Classes** - Combines and updates prototypes and object content
    * **Types & Grammar** - Refined and modernized
    * Some topics were consolidated or reimagined for clarity
  </Accordion>

  <Accordion title="Cancelled Topics" icon="circle-xmark">
    Some planned books were cancelled in the second edition:

    * **Sync & Async** - Cancelled as a standalone book
    * **ES.Next & Beyond** - Cancelled as modern features are integrated throughout

    These topics are covered within other books or omitted in favor of more relevant content.
  </Accordion>

  <Accordion title="New Publishing Model" icon="book-open">
    The second edition uses a different publishing approach:

    * Self-published through [GetiPub](https://geti.pub)
    * "The Unbooks" collection bundles later books together
    * Available on Leanpub and Amazon
    * Still freely readable on GitHub
  </Accordion>
</AccordionGroup>

## Which Edition Should You Read?

<CardGroup cols={2}>
  <Card title="Read Second Edition If..." icon="circle-check" iconType="solid" color="#fc9304">
    * You want the most current content
    * You're learning modern JavaScript (ES6+)
    * You prefer updated examples and explanations
    * You want the author's refined teaching approach
  </Card>

  <Card title="Reference First Edition If..." icon="clock-rotate-left" color="#f46404">
    * You're maintaining legacy JavaScript code
    * You want to see how topics were originally explained
    * You're comparing the evolution of concepts
    * You need coverage of pre-ES6 patterns
  </Card>
</CardGroup>

<Tip>
  For most readers, the **second edition** is recommended. It represents the author's latest thinking and is written for the JavaScript you'll use today.
</Tip>

## No Translations for First Edition

<Warning>
  Foreign language translations are only accepted for the **second edition** books. New translations of first edition content will not be accepted.
</Warning>

If you're interested in translating You Don't Know JS Yet, please see the [Contributing guide](/contributing) for information on translating the second edition.

## Legacy and Impact

The first edition of You Don't Know JS had an enormous impact on the JavaScript community:

* Over **150,000 stars** on GitHub (across both editions)
* Translated into dozens of languages
* Used in bootcamps and self-study programs worldwide
* Helped establish a culture of "deep learning" in JavaScript education

The second edition builds on this foundation while moving the content forward for the next generation of JavaScript developers.

<Note>
  The first edition books are complete and no longer being updated. All future development focuses on the second edition.
</Note>

## Access the First Edition

Ready to explore the original series?

<Card title="Visit First Edition on GitHub" icon="github" href="https://github.com/getify/You-Dont-Know-JS/blob/1st-ed/README.md" color="#fc9304">
  Read all six books of the first edition for free on GitHub
</Card>