What on earth is HTML5?
HTML5 is changing everything on the web as we know it, and most of us don’t have a clue how, and why. Most of us won’t know HTML5 when it jumps out of the browser window and hits us between the eyes with a hammer. We just assume it’s Flash.
Except, it’s not … quite … but we can’t quite put our fingers on it.
What on earth is HTML5?
HTML5 is an evolution, as opposed to a revolution. It is the next evolution of the web’s document format – HTML.
In the early 1990s, when the web was born, HTML was mainly a text document format. A typical argument in the drafting of HTML as a standard included whether images should be built into the browser, and called by name!
In other words, HTML was originally not designed to be a media rich format.
Over time the need arose to include not only images, but also video, audio, interactive graphs, and all kinds of rich media into web pages.
Flash stepped up and provided most of that functionality through a plug-in.
The downside was that the Flash content was binary (not readable by search engines), and as a whole, it provided very little along the lines of interacting with the rest of the page.
It was just an HTML page with a piece of Flash in it. Nothing more.
The most obvious solution HTML5 provides is new tags (keywords) that allows all kinds of media and graphical content to be included in an HTML5 page, in an open and interactive way.
A fantastic example is this music video Mirror, by Japanese band Sour.
This band is, by the way, not entirely new to the viral scene.
In HTML, all content is equal. Ads, menus, blog post content, titles, comments … they’re all enclosed in tags with the exact same semantic meaning.
In other words, web browsers and search engines cannot distinguish between them, and as a result, a comment on a blog post is being treated on par with the post content when Google tries to figure out what the post is about.
HTML5 introduces a whole range of new content container tags to add semantic spice to web content.
Without going into too much detail, these tags are placed around pieces of content, marking them as specific commonly used types of content.
A web browser or search engine not only knows that there is content now, but also knows more or less what the content represents.
Google now knows which part of the web page is the body text of an article. It knows where the paragraph breaks are – it knows where the article stops and where the comments start. This is used to provide better search results, by understanding document structure.
This is not possible with HTML4.
An even more exciting evolution on the semantic front is microdata.
Microdata allows the author of a web page to define a set of additional data values to enhance the meaning of pieces of information. Google already uses this.
Microdata can for instance be used to, on a user profile page, tell Google (or any browser that implements microdata) which part of the content is the user’s name, which part is their profile picture, and which part is their email address.
In the same way, microdata can be used on an event page to tell Google when the event starts, and how long it will carry on for. This is being used today, and it works.
What can HTML5 do?
Let’s start this section by asking a counter question: What can HTML do?
The answer is: Nothing.
It is not supposed to do anything – it merely tells a browser what to display. HTML5 is different.
Interactivity – the HTML5 APIs
A canvas element can for instance be turned into a game screen, and updated just like a screen. In other words, anything that could traditionally only be done natively on the Operating System, can now be done in a canvas element in the browser.
The Messaging API can be used to communicate between different elements or objects on a page, and even between different browser windows. As shown with the music video mentioned above, this allows for multi window applications that do things in perfect sync. Browser windows can message each other and send data to each other, behaving as a single application.
All of these additions fill all the necessary gaps to turn the browser into the new platform. This vision is clear when considering Google’s Chrome OS, which is nothing more than an Operating System that consists entirely of only one application: Google Chrome.
This bridges the gap between different Operating Systems, between Mobile and Desktop. It achieves what Sun tried to do with Java. A truly abstract platform, which behaves exactly the same, no matter which system it is running on.
Posted by Adriaan Pelzer