The JavaScript Handbook (2025 edition)
One of my most popular handbooks is the JavaScript Handbook. Understandably, as JavaScript is such a popular programming language.
I first released this in 2020, 5 years ago.
Today I’m releasing an update.
Not much changed in the language, to be honest. JavaScript is super stable these days.
It’s mostly just cosmetic updates and minor / accuracy fixes, and clarifications, to make this book even better than it already was, and to make it up to date for the next 5 years!
Here’s a brief list of changes:
- Fixed some code examples
- Fixed some grammar and poor wording choices
- Modernized async content
- Type coercion clarification
- Improved how I explain arrays, and objects
- Clarified when you can omit braces in arrow functions (single statement)
- Consolidated default-parameter wording.
- Improved
const/letconsistency:constfor non-reassigned bindings,letonly when reassigned. - Kept semicolon style consistent (no semicolons).
Download it now from https://flaviocopes.com/access/
I wrote 20 books to help you become a better developer:
- JavaScript Handbook
- TypeScript Handbook
- CSS Handbook
- Node.js Handbook
- Astro Handbook
- HTML Handbook
- Next.js Pages Router Handbook
- Alpine.js Handbook
- HTMX Handbook
- React Handbook
- SQL Handbook
- Git Cheat Sheet
- Laravel Handbook
- Express Handbook
- Swift Handbook
- Go Handbook
- PHP Handbook
- Python Handbook
- Linux/Mac CLI Commands Handbook
- C Handbook