There is a language identified with HTML called Extensible Markup Language (XML) that software engineers use to make their own tags. It’s broadly utilized for Web databases, for instance, since it can characterize tags for every information field. Since XML can be so totally redid, software engineers can make practically some other markup language inside it, just by re-making all the authoritatively acknowledged labels of that language.
The W3C did only that: they re-made the whole HTML language in XML, and called it Extensible HTML (XHTML). Rendition 1.0 was discharged in 2001; the current rendition is XHTML 2.0, discharged in 2004.
XHTML, at that point, is HTML composed inside the bigger language of XML. Since it is for all intents and purposes indistinguishable from HTML in its usefulness, the fundamental arrangement of tags is the equivalent, and you can learn both HTML and XHTML simultaneously.
You can likewise utilize XHTML to make new tags and augmentations, which is an important element for cutting edge Web engineers
There’s only one thing about XHTML to keep an eye out for: it’s not open minded toward botches. For instance, in HTML, in fact you should start each section with <p> and end each paragraph with </p>. But in HTML you can leave out the closing tag if you want (or if you forget it). That won’t work in XHTML. There are lots of little ways that XHTML is picky like that.
Be that as it may, in HTML you can forget about the end tag in the event that you need (or on the off chance that you overlook it). That won’t work in XHTML. There are parts of little ways that XHTML is particular like that.
At a certain point, it was imagined that XHTML would in the end supplant HTML4 as its replacement, however because of interoperability issues, that has not occurred; HTML5 is ready to succeed HTML4. This book doesn’t expressly cover XHTML, however a large portion of what you will realize can be applied to XHTML coding.