webGL WebGL brings 3D graphics to the Web by introducing an API that closely conforms to OpenGL ES 2.0 and can be used in HTML5
HTML5 parsing liberates MathML and SVG from XML and makes them available in the main file format of the Web.
Link relations complement the <a> tag and specify why you're pointing to another page.
Form elements and attributes in HTML5 provide a greater degree of semantic mark-up than HTML4 and remove a great deal of the need for tedious scripting and styling that was required in HTML4.
Microformats allow web sites to provide semantic data to the browser in order to make it possible to present summaries of the information on a page without having to know how to parse the document itself.
See also: http://www.microformats.org
The HTML5 specification brings several new elements to web developers allowing them to describe the structure of a web document with a standard semantics.
Firefox supports the HTML 5 specification for offline caching of web applications' resources and offline storage of data.
IndexedDB is an evolving web standard for the storage of significant amounts of structured data in the browser and for high performance searches on this data using indexes.
Workers provide a simple means for web content to run scripts in background threads. Once created, a worker can send messages to the spawning task by posting messages to an event handler specified by the creator.
In order to build a good offline-capable web application, you need to know when your application is actually offline. Incidentally, you also need to know when your application has returned to an online status again.
Firefox and other Mozilla applications support a number of features for handling drag and drop. This allows you the user to click and hold the mouse button down over an element, drag it to another location, and release the mouse button to drop the element there.
It's fairly common to find web pages link to resources using non-
http protocols. You can think of this as a desktop-based protocol handler.
The Geolocation API allows the user to provide their location to web applications if they so desire. For privacy reasons, the user is asked to confirm permission to report location information.
The focus atributes let a script understand if an element has the focus of the user and then act accordingly.
The following page shows the CSS3 support in Firefox and the new elements for HTML5.
The following pages show some of the visual attributes introduced by CSS3.
CSS also introduces dynamic effects: