Hypertext Markup Language (HTML)5 introduces new elements into HTML for the first time. New structural elements include aside, figure, and section. New inline elements include time, meter, and progress. New inline elements include video and audio. New interactive elements are details, datagrid and command.
The development of Hypertext Markup Language (HTML) stopped in HTML 4 in 1999. The World Wide Web Consortium (W3C) shifts its focus to changing HTML's underlying syntax from the standard universal markup language (SGML) to Extensible Markup Language (XML), as well as new markup languages such as Scalable Vector Graphics (SVG), XForms, and MathML. Browser manufacturers focus on browser features such as tabs and rich site summary (RSS) readers. Web designers have begun to learn to build their own applications in existing frameworks using asynchronous JavaScript XML (Ajax). But in the next eight years, HTML itself has not changed.
Recently, it has been resurrected again. Three important browser manufacturers—Apple, Opera and Mozilla Foundation—set the Web Hypertext Application Technology Working Group (WhatWG) to develop new versions of traditional HTML. Recently, W3C has also paid attention to these activities and launched its own new generation HTML project, and many of the members of both sides are the same. The two projects are likely to eventually merge. Although many details are still being debated, the general outline of the next version of HTML is already clear.
Web developers have been expecting a new version of HTML since 1999 (often called HTML 5, but also called Web Applications 1.0), and now it's finally released. It keeps the original HTML feature: no namespace or schema. The element does not have to end. Browsers will be tolerant of mistakes. p is still p, table is still table.
If a web developer was frozen in 1999 and now he would encounter some new confusing elements. Yes, the elements he is familiar with (such as div) are still preserved; however, HTML now also contains new elements such as section, header, footer, and nav. em, code and strong still exist, but meter, time and m are added. img and embed are still available, but video and audio are also added. However, after a closer look, he found that these elements were actually no different. Many of these elements may have been needed by developers in 1999 and were not available. These new elements are easy to understand by making simple analogies with the elements he has grasped. In fact, they are very easy to grasp compared to Ajax or CSS.
Finally, when he opened a 300MHz notebook (which was running Windows 98, also frozen in 1999), he might be surprised by the new pages shown in Netscape 4 and Windows? Internet Explorer? 5. Of course, these old browsers are not familiar with the new elements and will ignore them completely, but the page will still show up and the content is still complete.
This is not a fictional story. HTML 5's design principle is to degrade smoothly in browsers that do not support it. The reason is simple: we are all such "primitive people". Browsers now have tabs, CSS, and XmlHttpRequest, but their HTML display engines remain at 1999 levels. Apart from the significant increase in the number of users, the Web has actually made little progress in nature. HTML 5 takes this into account. It currently offers some real benefits for web developers, which page viewers will gradually enjoy as the browser slowly upgrades.
Let's take a look at what HTML 5 provides.
(to be continued)