The scripting language used in WME is based on JavaScript. In fact it’s a very simplified version of JavaScript but extended by some features specific to game scripting and simultaneous processing of multiple scripts. If you are already familiar with JavaScript (or a similar programming language, such as Java, C++ or PHP) you should be able to start writing WME scripts almost immediately. Otherwise I recommend you study some programming literature. It’s beyond the scope of this document to teach you programming; the language features and constructs will be described very briefly.
Beginners are advised to take a look at metamorphium's scripting tutorials in WME Wiki: