The rest of this book contains a quick-reference for the core and client-side JavaScript APIs. It documents the complete core JavaScript API, covers the legacy (Level 0) DOM API, and presents a simplified view of the W3C Level 2 DOM API. Portions of that API not relevant to JavaScript programmers working with HTML documents have been omitted. The upper-right corner of the title block for each reference entry contains information that states whether a feature is part of the core or client-side API, and further indicates which version of JavaScript, which browsers, or which version of the DOM introduced the feature.

Because JavaScript is a loosely-typed language, there is not an official set of class names for the classes and objects of the JavaScript API, and they sometimes appear under different names in different references. (For brevity, this book actually uses a slightly different set of names than its big brother, JavaScript: The Definitive Guide.) The following table summarizes the reference entries that follow, and allows you to quickly scan for the class or object you are interested in.

Anchor	A named position in a document
Applet	A Java applet
Arguments	The arguments of a function
Array	Array creation and manipulation
Attr	An attribute of a document element
Boolean	A wrapper object for boolean values
Comment	An HTML comment
DOMException	Signals DOM errors
DOMImplementation	Creates documents, checks DOM features
Date	Manipulates dates and times
Document	An HTML document
DocumentFragment	Nodes to be manipulated together
Element	An HTML tag in a document
Error	Predefined exception types
Event	Event details
Form	An HTML input form
Function	A JavaScript function
Global	Global properties and functions
History	Browsing history
Image	An HTML image
Input	A form input element
Layer	An independent document layer
Link	An <a> or <area> link
Location	Current browser location
Math	Mathematical functions and constants
Navigator	Information about the browser
Node	A node in a document tree
Number	Support for numbers
Object	The superclass of all JavaScript objects
Option	A selectable option
RegExp	Regular expressions for pattern matching
Screen	Information about the display
Select	A graphical selection list
String	String manipulation
Style	Inline CSS properties of an element
Text	A run of text in a document
Textarea	Multiline text input
Window	Browser window or frame