The following features are defined in the WebCore.js module. These features are web-specific and generally only applicable to code that is interacting directly with the web browser.

Event Processor

The EventProcessor provides a means of registering event listeners that enables are browsers (including Internet Explorer) to support capturing and bubbling phases of event processing.

Measure

The Measuring API enables the developer to calculate the rendered on-screen size of an object.

Environment

The Environment API provides information about the client web browser, the user's operating system, and the user's locale (including timezone).

DOM Manipulation

The DOM Manipulation API provides a cross-platform interface to various DOM related operations that may be abnormally implemented in Internet Explorer.

HTTP Connection

HTTPConnection provides a cross platform XMLHttpRequest implementation that supports object-oriented event listeners (Method References).

Library Loading

The Library Loading API enables the developer to dynamically load new JavaScript code.

Unit Conversion

The Unit Conversion API determines the rendered size of all non-pixel values (e.g., picas, mm, inches, etc) such that all such units can be converted to pixels for pixel-perfect rendering.

Virtual Positioning

The Virtual Positioning system allows the developer to set CSS attributes on all four sides of a DOM element and achieve the correct rendering behavior with Internet Explorer 6. This browser normally only supports one horizontal and one vertical CSS positioning setting, i.e., only 'left' or 'right' may be set, and only 'top' or 'bottom' may be set.