Resources for Developers,
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Documenting web technologies, including CSS, HTML, and JavaScript, since 2005.

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CSS

Introducing the CSS Cascade

The cascade is an algorithm that defines how user agents combine property values originating from different sources. The cascade defines the origin and layer that takes precedence when declarations in more than one origin or cascade layer set a value for a property on an element.

HTML

<dialog>: The Dialog element

The <dialog> HTML element represents a dialog box or other interactive component, such as a dismissible alert, inspector, or subwindow.

JavaScript — Dynamic client-side scripting

Asynchronous JavaScript

In this module, we take a look at asynchronous JavaScript, why it is important, and how it can be used to effectively handle potential blocking operations, such as fetching resources from a server.

Web APIs

Canvas tutorial

This tutorial describes how to use the <canvas> element to draw 2D graphics, starting with the basics. The examples provided should give you some clear ideas about what you can do with canvas, and will provide code snippets that may get you started in building your own content.

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