HTML 5, platforms of online applications

To succeed to HTML 4, which is the current format of Web pages, the W3C, which sets the standards of the Net, has taken a specification started by the WHATWG.
This new format is implemented progressively by all browsers including Internet Explorer 9 is designed for Web applications and adds both new tags and new features. It is now an alternative to Flash and Silverlight.

Steve Jobs said for Apple:

"Apple does not support Flash because it is so buggy. Whenever a Mac crashes more often than not it’s because of Flash. No one will be using Flash. The world is moving to HTML5."
(Apple Town Hall Meeting, January 2010).

HTML 5 vs Flash and Silverlight

Extended capabilities for Web applications

Using Web applications offline is the major trend since 2008. A framework, Google Gears, has been created for that, now replaced by equivalent functions in HTML.
In offline mode pages and objects they display are cached and a local SQL database stores the data to duplcate the remote base.

New graphical component has been added, see the list of form objects in HTML 5 and their current implementation in browsers.
The input tag can represent more types of objects and has new features like auto-complete. Output displays the result of calculations.
The addition of constraints on the data helps to secure the forms.

Section, article, header, footer tags are intended to give structure to a document.
Dialog is an object formalizing a discussion and is associated to a label element.
HTML has now canvas, audio, video tags and many other new elements.

HTML 5 is designed for Web applications

Structure of an HTML 5 page
The tags required and new structure tags introduced with HTML 5.

Doctype
Which one to choose?

Div and span
Differences in practical use.

Select

• Option

Radio button
How to know what checkbox is thicked for Ajax scripts.

Contextual menu and toolbar

Table
How to organize tabular data.

InnerHTML and outerHTML
Accessing the content.

Comment
The HTML 5 tag, and conditional comments of Internet Explorer.

Iframe, for dynamic or sandboxed content

Canvas
This is a surface on which objects are displayed with JavaScript scripts.

FileReader
Loading a text or an image in a page, from the local file system.

The video tag

• Video codecs for HTML 5
  Ogg, WebM, H.264 and their implementation.

SessionStorage
Description and check for compatibility.

HTML 5 and applications