Ajax presents a new way of developing web applications that is more event-driven like typical client-server GUI applications. While Ajax uses technologies like JavaScript, XML, and CSS to asynchronously update parts of a page without reloading, the role of backends like Caché is reduced to basic data storage and retrieval. However, Caché remains well-suited for large, high-performance enterprise applications as they grow beyond what technologies like MySQL can easily support. Frameworks like EWD that define applications independently of technologies allow easier migration between backends like MySQL and Caché as applications scale.