Ajax in Practice Chapters 1 & 2 Examples

Hello World 1 Demonstrates using the Prototype Ajax helper classes to simplify an asynchronous Ajax request.
Hello World 2 Rather than returning plain text, we return preformatted HTML from the server.
Hello World 3 Return JavaScript from the server, and evaluate it on the client.
Hello World 4 Adopt a cleverer strategy toward server-side code generation, writing to a high-level API. We also begin to address the multiple update problem, whereby we want to update several elements from a single Ajax response.
Hello World 5 We return a structured data object from the server, defined using the JSON syntax that JavaScript readily understands.
Hello World 6 We return structured data as XML, which the server is more likely to understand! We parse the XML using DOM methods, which is not so pleasant.
Hello World 7 We make use of modern tools to handle the XML on the client, employing XPath queries and XSL transforms rather than the DOM methods.
Hello World 8 Invoke a web service from the JavaScript tier using Ajax.