You probably use it every day, yet there’s no standard implementation. It was introduced 10 years ago, but despite its age and widespread adoption
console is not part of ECMAScript.
Where did it come from? What did people do before
Writing to that console was the inspiration for
console.log. Without it, developers used a combination of
window.alerts and tools that wrote log messages to hidden DOM elements or attributes. One such tool was fvlogger released in 2005 by David F. Miller of A List Apart. Other tools with an interface similar to Apache log4j appeared in 2005, including log4js by Tim Down and JSLogger by Dan Allen.
console appears to have been first introduced in its current form in 2006 by Firebug, a web development plugin for Firefox. Firebug provided an enhanced web console capable of debugging, profiling, and DOM inspection. Similar plugins for other browsers appeared shortly after. These third-party development consoles put pressure on browsers to incorporate their features. Eventually, a console object was introduced in Internet Explorer 8, Opera 9.5, and Safari 3 (not confirmed).
Today still there is no standardized implementation of console object and its methods. Even
console.log behaves slightly different across browsers. It’s grown beyond the Firebug implementation, with methods for tables, timers, and stack traces. The Developer Tools Working Group has begun a draft console standard to improve parity between implementations. With widespread implementation across browsers and node.js, it looks like console is here to stay.