AHAH is intended to be a much simpler way to do web development (http://en.wikipedia.org/wiki/Web_development) than AJAX (http://en.wikipedia.org/wiki/Ajax_%28programming%29): "Asynchronous JavaScript and XML." Strictly speaking, AHAH can be considered a subset of AJAX, since (X)HTML is just a special kind of XML. However, it is a subset with some very specific and useful properties:

1. The lack of custom XML schemas dramatically reduces design time
2. AHAH can trivially reuse existing HTML pages, avoiding the need for a custom web service
3. All data transport is done via browser-friendly HTML, easing debugging and testing
4. The HTML is designed to be directly embedded in the page's DOM, eliminating the need for parsing
5. As HTML, designers can format it using CSS, rather than programmers having to do XSLT transforms
6. Processing is all done on the server, so the client-side programming is essentiall nil (moving opaque bits)