All of the browser's support the ECMA standard edition3 released in 1999. This is the industry standard that was created as the baseline model. Since this is not updated very often and browsers are made by different companies with different philosophies we are left with many "flavors" of this language. The ECMA version 4 was slated to be released last October. It was going to have classes, namespaces, and a host of other features. This is what the ECMA posted on their web site:
The fourth edition of the ECMAScript language (ES4) represents a significant evolution of the third edition language (ES3), which Ecma approved as the standard ECMA-262 in 1999. ES4 is compatible with ES3 and adds important facilities for programming in the large (classes, interfaces, namespaces, packages, program units, optional type annotations, and optional static type checking and verification), evolutionary programming and scripting (structural types, duck typing, type definitions, and multimethods), data structure construction (parameterized types, getters and setters, and meta-level methods), control abstraction (proper tail calls, iterators, and generators), and introspection (type meta-objects and stack marks
Here is a table that shows the current market implementations.
|Vendor||Browser||Layout Engine||Scripting Engine||Scripting Language|
|Microsoft||Internet Explorer 7||Trident||JScript||JScript|
On a positive note for standards, Microsoft announced that they are supporting Jquery as part of it's official platform. This means better cross-browser support for web site programmers.
Figure 1) Dialects
Figure 2) Scripting Languages