Overview

AJAX

• Asynchronous JavaScript and XML
• Combines client-side processing and server-side technologies
• Client-side processing uses javascript
• XML is often the language for passing data, although Rails generally uses JSON (Javascript Object Notation) as the language for passing data.
• Produces more responsive user interactions

Other terminology

• Rich Internet Applications (RIAs) --- these web applications provide interactive user actions similar to those provided by a desktop application (e.g. drag and drop).
• Web 2.0 --- refers to a second generation of web applications, especially involving user-provided content. These applications often make use of rich interactions required for WYSIWYG editors.

AJAX and Rails

In Rails 2, many AJAX processes could be deployed in Rails using Ruby method calls. Coding in Javascript and JSON was not needed. However, Rails 3 calls for more explicit use of javascript when responding to requests. Fortunately, the increasing us of the jQuery library makes the javascript coding easier.