ES6 stands for ECMAScript 6, which is a new version of the JavaScript language specification. It was released in 2015 and introduced many new features and improvements to the language, making it more powerful and easier to use.

Some of the new features introduced in ES6 include:

1. Arrow functions: A shorter syntax for writing functions, making code more concise and easier to read.

2. Template literals: A way to interpolate variables into strings using backticks (`), making string manipulation easier.

3. Let and const declarations: New ways to declare variables with block scope, making code more predictable and less error-prone.

4. Classes: A more structured way to define object-oriented programming in JavaScript.

5. Enhanced object literals: Simplified syntax for creating and initializing objects.

6. Promises: A new way to handle asynchronous operations, making code more readable and easier to maintain.

Overall, ES6 is a major upgrade to JavaScript, and it has greatly improved the language by introducing many new features and improvements.