If you are still using regular HTML to create your websites, then you’ve fallen behind the times. XHTML can give you greater control over the appearance of your site’s content. In many ways, it is also a simplified version of HTML that makes it easier for developers to create design elements from scratch. Before you can start using XHTML, though, you will need to know some of the functional differences between it and HTML.
Moving on From HTML
Those who already know HTML will find that learning XHTML is easy. On some pages, you might not even notice a big difference between the two systems. The relationship between the two markup languages exist for a reason: XHTML was built from HTML so that designers could use the skills that they already had just by picking up a few extra pieces of information.
Writing XHTML Tags
One of the fundamental differences between using HTML and XHTML is that you cannot leave any elements open in XHTML. With HTML, you could easily bold a whole page just by including the <b> tag before the first word. As long as you did not close the instructions before the last word, it would bold the entire page. With XHTML, you need to close the element. That’s simply because XML requires an opening and closing for every element. It can also help keep your tags better organized because every element has a compliment.
Failing to close XHTML tags will render a web page useless. HTML would produce pretty much any garbled mess that someone could type into an .rtf document. XHTML is a little more particular with what it displays.
Unlike HTML, XHTML is case-sensitive. If you have been using HTML for a long time, then you might have to consciously force yourself to pay attention to cases. It doesn’t take very long to pick up the case-sensitive habit, though.