The level 2 DOM is an enhancement on the level 1 support. It introduces additional properties and styles for document objects.
The standard is composed of the following modules:
DOM core functionality
Traversal and range specification
The DOM level specification is now a 500 page document that maps the HTML specification to the ECMAScript and Java language bindings. Many additional objects are provided to assist in navigating the DOM hierarchy.
In general, the MSIE version 5 browser on Windows and Macintosh is the best and most complete implementation of DOM released for general use so far.
Netscape 5 never saw the light of day, and with Netscape 6, the development teams have a stated goal of going very aggressively for DOM standardization. Running the same inspection scripts on MSIE 5 and Netscape 6 reveals that the DOM implementations are structurally similar but that the DOM compliance is more robust in Netscape . This is because MSIE does not use the standardized class names fpr objects although the entity relations are more or less correct.
The differences between level 1 and level 2 basic support for DOM are as follows:
Some new methods added to the existing DOM interfaces and exceptions. This extends to about 30 minor changes.
Many wholly new interfaces are added. These provide access to the HTML implementation, views on the document, additional StyleSheet support, new CSS support, Event handling support, traversals and ranges.