What is the doctype declaration of html5

The doctype declaration of html5 is "fef50554eca1a427827adaa329da8122", which is an instruction used to inform the browser that the document uses the HTML specification. The doctype declaration must be on the first line in the HTML5 document, before the "100db36a723c770d327fc0aef2ce13b1" tag.

The operating environment of this tutorial: Windows 7 system, HTML5 version, Dell G3 computer.

HTML5 DOCTYPE declaration

DOCTYPE is the abbreviation of document type.

The doctype declaration is not an HTML tag; rather, it is a document type tag, which is an instruction that tells the browser the version of markup in which the page was written.

The doctype declaration is a document type declaration in a standard universal markup language. It is used in web design to indicate what version of XHTML or HTML you are using.

html5 There is only one doctype declaration:

1a309583e26acea4f04ca31122d8c535 The declaration must be located on the first line in the HTML5 document, that is, before the 100db36a723c770d327fc0aef2ce13b1 tag. This tag tells the browser the HTML specification used by the document.

     
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It is very important to specify the doctype in all HTML documents so that the browser understands the expected document type.

Explanation:

• 1a309583e26acea4f04ca31122d8c535 tag has no closing tag.

• 1a309583e26acea4f04ca31122d8c535 is not case sensitive.
  

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