JavaScript, created by Brendan Eich in 1995, has evolved significantly over the years. It became an ECMA standard in 1997, and the official name of the language is ECMAScript. The versions of ECMAScript are abbreviated as ES1, ES2, ES3, ES5, and ES6, with subsequent versions named by the year of release.

Key Versions and Features

ECMAScript 1 (1997)

The first edition of ECMAScript, which laid the foundation for the language.

ECMAScript 2 (1998)

Introduced minor editorial changes.

ECMAScript 3 (1999)

Added several important features:

• Regular expressions

• try/catch for exception handling

• switch case and do-while loops

ECMAScript 5 (2009)

A significant update that introduced:

• Strict mode: Enforces stricter parsing and error handling of JavaScript code.

• JSON support: Methods for parsing and stringifying JSON data.

• New array methods: Array.isArray(), Array.forEach(), Array.map(), Array.filter(), Array.reduce(), and more.

ECMAScript 2015 (ES6)

A major update with numerous new features:

• let and const: Block-scoped variable declarations.

• Arrow functions: Shorter syntax for writing functions.

• Classes: Syntactic sugar over JavaScript's prototype-based inheritance.

• Template literals: Enhanced string literals with embedded expressions.

• Default parameters: Allow function parameters to have default values.

• Destructuring assignment: Unpack values from arrays or properties from objects into distinct variables.

• Modules: import and export statements for modular code.

• Promises: Simplified handling of asynchronous operations.