To get your feet wet means to try something out for the first time to see how it feels. Just as you might dip your feet into a lake before you decide whether to go for a swim, you can use a Get Your Feet Wet guide to try a little of something before you fully commit yourself to it.
The Get Your Feet Wet Guide to XML explores the basic concepts of XML and includes a tutorial exercise so you can try coding a simple XML document yourself. The guide is not meant to be a comprehensive resource, but rather a quick way for you to learn some basics before you decide whether to dive into the complexities of XML.