It is said that one picture is worth a thousand words. And so is a well-written piece of code, we would say. In this chapter you will get plenty of both, while learning the foundations of client-side AJAX development.
Hopefully, the first chapter has developed your interest in AJAX well enough that you will endure the second chapter with lots of theory to be learned. On the other hand, if you found the first exercise too challenging, be assured that this time we will advance a bit slower. We will learn the theory in parts by going through many short examples. In this chapter, we will meet client AJAX technologies, which include:
JavaScript
The Document Object Model (DOM)
Cascading Style Sheets (CSS)
The
XMLHttpRequest
object
You will learn how to make these components work together smoothly, and form a strong foundation for your future AJAX applications.