HTML 5 Draft

We have been using HTML 4.01 and XHTML 1.0 for a long time. And the draft of HTML 5 was published a month ago. There are several new tags that I suppose you will like. For example <input type="number" /> will show up an input control that your visitor may only enter some numeric value. That sounds really cool! You may read a short list of changes/improvements below but that is not the complete list for sure.

The following elements have been introduced for better structure:

section represents a generic document or application section. It can be used together with h1–h6 to indicate the document structure.

article represents an independent piece of content of a document, such as a blog entry or newspaper article.

aside represents a piece of content that is only slightly related to the rest of the page.

header represents the header of a section.

footer represents a footer for a section and can contain information about the author, copyright information, et cetera.

nav represents a section of the document intended for navigation.

dialog can be used to mark up a conversation like this:

<dialog>
 <dt> Costello
 <dd> Look, you gotta first baseman?
 <dt> Abbott
 <dd> Certainly.
 <dt> Costello
 <dd> Who's playing first?
 <dt> Abbott
 <dd> That's right.
 <dt> Costello
 <dd> When you pay off the first baseman every month, who gets the money?
 <dt> Abbott
 <dd> Every dollar of it. 
</dialog>

figure can be used to associate a caption together with some embedded content, such as a graphic or video:

<figure>
 <video src=ogg>…</video>
 <legend>Example</legend>
</figure>

Then there are several other new elements:

audio and video for multimedia content. Both provide an API so application authors can script their own user interface, but there is also a way to trigger a user interface provided by the user agent. source elements are used together with these elements if there are multiple streams available of different types.

embed is used for plugin content.

m represents a run of marked text.

meter represents a measurement, such as disk usage.

time represents a date and/or time.

canvas is used for rendering dynamic bitmap graphics on the fly, such as graphs, games, et cetera.

command represents a command the user can invoke.

datagrid represents an interactive representation of a tree list or tabular data.

details represents additional information or controls which the user can obtain on demand.

datalist together with the a new list attribute for input is used to make comboboxes:

<input list=browsers>
<datalist id=browsers>
 <option value="Safari">
 <option value="Internet Explorer">
 <option value="Opera">
 <option value="Firefox">
</datalist>

The datatemplate, rule, and nest elements provide a templating mechanism for HTML.

event-source is used to "catch" server sent events.

output represents some type of output, such as from a calculation done through scripting.

progress represents a completion of a task, such as downloading or when performing a series of expensive operations.

The input element’s type attribute now has the following new values:

• datetime
• datetime-local
• date
• month
• week
• time
• number
• range
• email
• url

The idea of these new types is that the user agent can provide the user interface, such as a calendar date picker or integration with the user’s address book and submit a defined format to the server. It gives the user a better experience as his input is checked before sending it to the server meaning there is less time to wait for feedback.

And of course there are new attributes and changes within the currently existing attributes.

HTML 5 has introduced several new attributes to various elements that were already part of HTML 4:

The a and area elements now have a media attribute for consistency with the link element. It is purely advisory.

The a and area elements have a new attribute called ping that specifies a space separated list of URIs which have to be pinged when the hyperlink is followed. Currently user tracking is mostly done through redirects. This attribute allows the user agent to inform users which URIs are going to be pinged as well as giving privacy-conscious users a way to turn it off.

The area element, for consistency, now has the hreflang and rel attributes.

The base element can now have a target attribute as well mainly for consistency with the a element and because it was already widely supported. Also, the target attribute for the a and area elements is no longer deprecated, as it is useful in Web applications, for example in conjunction with iframe.

The value attribute for the li element is no longer deprecated as it is not presentational. The same goes for the start attribute of the ol element.

The meta element has a charset attribute now as this was already supported and provides a nicer way to specify the character encoding for the document.

A new autofocus attribute can be specified on the input (except when the type attribute is hidden), select, textarea and button elements. It provides a declarative way to focus a form control during page load. Using this feature should enhance the user experience as the user can turn it off if he does not like it, for instance.

The new form attribute for input, output, select, textarea, button and fieldset elements allows for controls to be associated with more than a single form.

The input, button and form elements have a new replace attribute which affects what will be done with the document after a form has been submitted.

The form and select elements (as well as the datalist element) have a data attribute that allows for automatically prefilling of form controls, in case of form, or the form control, in case of select and datalist, with data from the server.

The new required attribute applies to input (except when the type attribute is hidden, image or some button type such as submit) and textarea. It indicates that the user has to fill in a value in order to submit the form.

The input and textarea elements have a new attribute called inputmode which gives a hint to the user interface as to what kind of input is expected.

You can now disable an entire fieldset by using the disabled attribute on it. This was not possible before.

The input element has several new attributes to specify constraints: autocomplete, min, max, pattern and step. As mentioned before it also has a new list attribute which can be used together with the datalist and select element.

input and button also have a new template attribute which can be used for repetition templates.

The menu element has three new attributes: type, label and autosubmit. They allow the element to transform into a menu as found in typical user interfaces as well as providing for context menus in conjunction with the global contextmenu attribute.

The style element has a new scoped attribute which can be used to enable scoped style sheets. Style rules within such a style element only apply to the local tree.

The script element has a new attribute called async that influences script loading and execution.

The html element has a new attribute called manifest that points to an application cache manifest used in conjunction with the API for offline Web applications.

Several attributes from HTML 4 now apply to all elements. These are called global attributes: class, dir, id, lang, tabindex and title.

There are also several new global attributes:

The contenteditable attribute indicates that the element is an editable area. The user can change the contents of the element and manipulate the markup. The contextmenu attribute can be used to point to a context menu provided by the author. The draggable attribute can be used together with the new drag & drop API. The irrelevant attribute indicates that an element is not yet, or is no longer, relevant. </LI>

The following are the attributes for the repetition model. These are global attributes and as such may be used on all HTML elements, or on any element in any other namespace, with the attributes being in the http://www.w3.org/1999/xhtml namespace.:

• repeat
• repeat-start
• repeat-min
• repeat-max

HTML 5 also makes all event handler attributes from HTML 4 that take the form onevent-name global attributes and adds several new event handler attributes for new events it defines, such as the onmessage attribute which can be used together with the new event-source element and the cross-document messaging API.

If you are interested of reading the differences between HTML 4.01 and HTML 5, you may visit http://www.w3.org/TR/html5-diff/.