This isn't a big shake-up like HTML 4. See what it's all about below. Page Navigation: Why the Change? This page was last updated on Right, before we get into all this, you should have a good grasp of the ancient and more recent past of HTML. HTML began as a simple way to transfer data between any computer across the Internet; designed for scientists and researchers with no publishing experience.
Over time the web became mainstream entertainment and new tags were brought in by the browser companies that didn't go along with this original aim — presentation became hugely important and structure and compatibility started to take a back seat. This meant that some pages were not accessible for people with the 'wrong' browser or computer setup. Thankfully, the use of much of the extraneous presentational tags has receded in use in recent times, mainly due to the innovation of CSS code.
Ideal HTML would be purely structural , with every element concerning how a page is displayed being controlled by a stylesheet. Further to all that, in recent times the Internet has begun to be accessed through new devices other than the classic computer and web browser arrangement. Things like PDAs , phones and, er, fridges with Internet access are going to become common in the near future.
The custom-made browsers used in these systems need to be small for cost-effectiveness. For every markup error that a browser has to deal with, more code has to be added to the program. XHTML is a very, very strict way of coding , which means the system makers don't have to accommodate for bad markup. All web Markup languages are based on SGML , a horrendously complicated language that is not designed for humans to write.
SGML is what is called a metalanguage ; that is, a language that is used to define other languages. XML is a powerful format — you create your own tags and attributes to suit the type of document you're writing. By using a set group of tags and attributes and following the rules of XML, you've created a new Markup language.
The pre-existing HTML 4. This gives you all the benefits of XML see below , while avoiding the complications of true XML; bridging the gap for developers who might not fancy taking on something as tricky as full-on XML.
Its behavior is more predictable than HTML and it conforms to logical mark up rules thereby avoiding errors that make other pages fail in some browsers. XHTML eliminates the need to make multiple versions of a Web site so that it will be viewed the same in different browsers. Make sure all tags are in lowercase type. Make sure you quote all attribute values within the document.
Make sure you close all tags. All style for the website is contained in external CSS files. Transitional allows inline styles to be applied to elements. XHTML websites should define the default namespace. A namespace defines all of the elements you can use within the page.
Setting a default language allows a screen reader to tell the visitor which language the page is in without even seeing the content. It is also required by W3C standards. The http-equiv meta tag is by far the most important.
The language meta tag is important for non-English websites, but it has become common practice to include it on every page, despite the language. The description and keywords meta tags are required more for accessibility than to meet standards because they are commonly used by screen readers. Allow users to easily identify what page and sub-section of a page they are viewing. A majority of websites today use a combination of text, colors and graphic styles to organize and display information.
Many people with disabilities cannot see or use graphics and thus rely on screen readers, custom style sheets and other accessibility tools to retrieve information. Instead, HTML5 will be continually updated with new features, without version number changes. Broken down, it is a very flexible way to create information formats and then electronically share structure data on the Internet.
So, in some sense, the language is making it easier for all of us to read and understand data. However, while HTML is for showing us what data looks like on a web page, XML is what is used to carry, transport, and store all of the information. In XML, you define your own tags and it is self-descriptive. Now comes the kicker. It comes with the file extensions of. XHTML and. However, the main reason behind launching the language was to give people the ability to extend the HTML language.
So that it could be used for all data formats by use of XML. Originally, XHTML documents looked a lot more professional and helped get rid of bad coding habits that hindered web pages. However, that did not happen as HTML5 came along, and we will talk about that in a little bit.
The thought was that it would help negate poor code and cut down on errors. It also looked more professional when completed. However, some of the major benefits of it included the fact that it was supported on existing browsers and all new browsers. This meant that there were fewer compatibility issues when using it. It can also be edited, validated, and viewed with XML tools.
The language does well with providing a consistent formatting and well-designed structure for web pages. There you go, we have a detailed look at all three.
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