JavaScript language attribute

Occasionally I’ve stumbled upon legacy javascript code that is used to determine javascript support by the visiting users. This often proves comical, because they are many times wasting time making checks for some “VERY OLD” browsers indeed! Here’s a rundown of the versions of javascript as well as their release dates and some common browser versions that implemented them.

  • JavaScript 1.0 (March 1996) = Navigator 2.0 / MSIE 3.0
  • JavaScript 1.1 (August 1996) = Navigator 3.0
  • JavaScript 1.2 (June 1997) = Navigator 4.0-4.05
  • JavaScript 1.3 (October 1998) = Navigator 4.06-4.7x / MSIE 4.0
  • JavaScript 1.4 = Netscape Server
  • JavaScript 1.5 (November 2000) = Navigator 6.0 / Firefox 1.0 / MSIE 5.5 – 8.0 / Safari 3.0-5 / Chrome 1.0-10.x / Opera 6.0
  • JavaScript 1.6 (November 2005) = Firefox 1.5
  • JavaScript 1.7 (October 2006) = Firefox 2.0
  • JavaScript 1.8 (June 2008) = Firefox 3.0 / Opera 11.50
  • JavaScript 1.8.1 = Firefox 3.5
  • JavaScript 1.8.2 (June 2009) = Firefox 3.6
  • JavaScript 1.8.5 (July 2010) = Firefox 4.0 / MSIE 9.0 / Opera 11.60

The language attribute has long been deprecated and should generally be avoided, it’s original purpose was to support other scripting languages, notably VBScript, or particular JavaScript versions. Modern conventions rely on specifying the MIME type instead via the ‘type’ attribute.

<SCRIPT LANGUAGE="JavaScript"> is now <script type="text/javascript">

<SCRIPT LANGUAGE="JavaScript1.1"> is now <script type="text/javascript1.1">

<SCRIPT LANGUAGE="VBScript"> is now <script type="text/vbscript">

<SCRIPT LANGUAGE="TCL"> is now <script type="text/tcl">

REFERENCES:

Cross-browser Copy To Clipboard Functionality

Due to various security models, it can be difficult to create a simple way to copy data from a browser application into the OS’es “clipboard” with simple javascript. There are several libraries out there to assist in making this work across various platforms, most utilize Flash.

Here are a few notable methods:

Browser Rendering Engines

This is knowledge that is generally “tribal” by nature, reserved to only the nerdiest web developers, recently I was asked to name these and failed. Here’s the bounty of my research.

Gecko is generally considered to be the second most-popular layout engine on the Web, after Trident (used by Internet Explorer for Windows since version 4), and followed by WebCore (used by Safari) and Presto (used by Opera).

Gecko is the open source, free software web browser layout engine used in all Mozilla-branded software and its derivatives, including later Netscape browser releases. Written in C++ and licensed under MPL/GPL/LGPL triple license, Gecko is designed to support open Internet standards. Originally created by Netscape Communications Corporation, its development is now overseen by the Mozilla Foundation.

Trident (also known as MSHTML) is the name of the layout engine for the Microsoft Windows version of Internet Explorer. It was first introduced with the release of Internet Explorer version 4 in October 1997, has been steadily upgraded and remains in use today. For version 7 of Internet Explorer, Microsoft made significant changes to the Trident layout engine to improve compliance with web standards and add support for new technologies. Despite these changes, Trident remains significantly less compliant than competing layout engines Gecko, Presto and WebCore.

Presto is the name of the current (Opera 9 series) layout engine for the Opera web browser developed by Opera Software. It was first released (following several public betas and technical previews) on January 28, 2003 in Opera 7.0 for Windows. Presto replaced the Elektra engine used in versions 4–6 of Opera. Presto differs from Elektra in that it is dynamic: the page or parts of it can be re-rendered in response to DOM and script events. The Presto layout engine is only available as a part of Opera browser or related products. The source or binary (DLL) forms of the engine are not publicly available. Subsequent releases have seen a number of bugs fixed and optimizations to improve the speed of the ECMAScript (“JavaScript“) engine.

Tasman is the name of the layout engine introduced with version 5 of Internet Explorer for Mac. Tasman was an attempt to improve support for web standards, as defined by the World Wide Web Consortium. At the time of its release, Tasman was seen as the layout engine with the best support for web standards such as HTML and CSS. Unfortunately, MSIE for Mac is no longer supported, but newer versions of Tasman are incorporated in some other current Microsoft products.

Cheers!