In this example, we use XHTML, SVG, JavaScript, and the DOM to animate a swarm of "motes". These motes are governed by two basic principles. First, each mote tries to move towards the mouse cursor, and second each mote tries to move away from the average mote position. Combined, we get this very natural-looking behavior.

The constructor data property of an Object instance returns a reference to the constructor function that created the instance object. Note that the value of this property is a reference to the function itself, not a string containing the function's name.

The reduceRight() method of Array instances applies a function against an accumulator and each value of the array (from right-to-left) to reduce it to a single value.

This chapter documents all of JavaScript's standard, built-in objects, including their methods and properties.

This chapter introduces how to work with strings and text in JavaScript.

JavaScript is a prototype-based language — an object's behaviors are specified by its own properties and its prototype's properties. However, with the addition of classes, the creation of hierarchies of objects and the inheritance of properties and their values are much more in line with other object-oriented languages such as Java. In this section, we will demonstrate how objects can be created from classes.

The encodeURIComponent() function encodes a URI by replacing each instance of certain characters by one, two, three, or four escape sequences representing the UTF-8 encoding of the character (will only be four escape sequences for characters composed of two surrogate characters). Compared to encodeURI(), this function encodes more characters, including those that are part of the URI syntax.

The panose-1 attribute indicates the Panose-1 number of a font face.

A block statement is used to group zero or more statements. The block is delimited by a pair of braces ("curly braces") and contains a list of zero or more statements and declarations.

The class declaration creates a binding of a new class to a given name.