HyperText Markup Language (HTML) is the simplest method of formatting content on the web. It was initially introduced as a text-only markup system back in 1991. But with time, it went through different phases, and HTML has now evolved significantly.
The protocol helps the web designer add audio, text, video graphics and interactions to the web pages.
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XHTML is a developed form of HTML. It represents an evolutionary step to make web content easier to locate, analyse and retrieve. It insists that the documents produced with it, follow the rules strictly.
For example, all its elements must be closed as well as in lower case. The method also ensures that the entire family of its elements is properly nested.
This markup language system was developed purely to make web browsing easier. It was not perhaps that difficult for the developers. All they did was to add the data structuring capacities of XHTML to the formatting properties of HTML.
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