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JavaScript
Use these sections for debugging workflows, mini projects, version notes, and reference lookups.
When executing JavaScript code, different errors can occur.
Many beginners quit because they cannot debug .
JavaScript statements start with a statement identifier to identify the action to be performed.
In this project you will build a counter with buttons to:
ECMAScript 2026 introduces several features focused on improving resource management, handling asynchronous operations, and enhancing data manipulation:
JavaScript can fail siently.
The browser console is the most important debugging tool for JavaScript beginners.
Words marked with* have been added to JavaScript from after 2015.
This is a copy of the previous project.
The 16th edition of the ECMAScript standard, released in June 2025 , includes several enhancements to make JavaScript more readable and efficient.
In JavaScript, the try statement is used to handle errors (also called exceptions ) that may occur during code execution - without stopping the entire program.
Breakpoints let you pause JavaScript and inspect what is really happening.
Operator precedence describes the order in which operations are performed in an arithmetic expression.
In this project you will build a To-Do List .
These features are relatively new.
JavaScript error messages look scary, but most of them mean very simple things.
A modal is a popup window that appears on top of the page.
ECMAScript 2023 is supported in all modern browsers since July 2023 :
Async bugs are the hardest bugs for beginners.
In this project you will build a form with validation.
Supported in all modern browsers since March 2023 .
ECMAScript 2021 is supported in all modern browsers since April 2021 :
ECMAScript 2020
ECMAScript 2019
ECMAScript 2018
JavaScript 2017 is supported in all modern browsers since September 2017 :
Supported in all modern browsers since March 2017 .
The second major revision to JavaScript .
The first major revision to JavaScript .
The first revision to JavaScript .
The current JavaScript version is ES2025 .
JavaScript was invented by Brendan Eich in 1995.