PHPBuilder has posted the second part in their "XMLHttpRequest and AJAX for PHP programmers" series.

This week's article takes off where last week's tutorial left off--we're about to jump into the creation of the PHP backend! If you haven't read the previous article, we recommend that you begin there before moving forward so you don't miss anything.

They build on the first article, enhancing the abilities of the sample script by adding the PHP backend script that echoes out the appropriate products back to the XMLHttpRequest object. It grabs the $_GET request and displays the corresponding grouping of products. It's a very simple example, but it does well to illustrate how the two sides can work together.