Differences Between XHTML and HTML
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W3Schools

Abstract:

XHTML is the next generation of HTML, but it will of course take some time before browsers and other software products are ready for it. In the meantime there are some important things you can do to prepare yourself for it. As you will learn from this tutorial, XHTML is not very different from HTML 4.01, so bringing your code up to 4.01 standards is a very good start. Our complete HTML 4.01 reference can help you with that. In addition, you should start NOW to write your HTML code in lowercase letters, and NEVER make the bad habit of skipping end tags like the

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