Core JavaScript 1.5 Reference - MDC. Core JavaScript 1.5 Guide - MDC. The JavaScript Guide shows you how to use JavaScript and gives an overview of the language. If you need exhaustive information about a language feature, have a look at the JavaScript reference. This Guide is divided into the following chapters. Introduction Grammar and types Control flow and error handling Loops and iteration Functions Expressions and operators Numbers and dates Text formatting Indexed collections Keyed collections Working with objects Details of the object model Promises Iterators and generators. Eloquent JavaScript -- interactive tutorial. jQuery: The Write Less, Do More, JavaScript Library.