December 3, 2009
JavaScript ES5 standardized
On December 3, 2009, the ES5 standard was adopted — adding strict mode, built-in JSONJavaScript Object Notation — a lightweight text format for structured data exchange on the web. support, and safer object handling to JavaScript.
What it was for
ES5 was the first major JavaScript update in ten years. Strict mode (`"use strict"`) caught common bugs; built-in `JSONJavaScript Object Notation — a lightweight text format for structured data exchange on the web..parse` and `JSONJavaScript Object Notation — a lightweight text format for structured data exchange on the web..stringify` replaced third-party libraries; getters and setters enabled cleaner APIs. It was what jQuery-era websites ran on before modern JavaScript (ES6) became mainstream.
Why it's here
ES5 was the first meaningful JavaScript update in a decade and fixed real inconsistencies between browsers.
Why it mattered
Developers could parse JSONJavaScript Object Notation — a lightweight text format for structured data exchange on the web. natively and write stricter, less buggy code — without waiting years for the bigger ES6 overhaul.
What it solved
A failed ES4 rewrite had frozen the language; browsers and developers needed practical improvements they could ship now.
Media
- ImageECMAScript
Andrejus Ševcovas, Public domain, via Wikimedia Commons
Related
- JavaScript ES3 standardizedDecember 1999
- JavaScript ES6 standardizedJune 17, 2015