There are three cornerstones:
1. An AJAX-based event-driven engine
2. A rich set of XUL and XHTML components
3. ZUML (ZK User Interface Markup Language)
Before we go on, we should get familiar with a few buzzwords, which we mentioned before.
XHTML is the abbreviation of Extensible HyperText Markup Language. XHTML is very similar to HTML. Briefly, XHTML is HTML written in XML syntax. The following points are the most important differences:
The notation (uppercase/lowercase) of an element/attribute ...