HTML 5 Programming and Web development/HTML 5 Doctype

The HTML 5 Document Type Definition (Doctype) is used to identify the type of markup document. conventionally doctypes are written like this

<!doctype root-element PUBLIC [FPI] [URI]>

Where in this case the root-element would be HTML.FPI stands for formal public identifier. However in HTML 5 the Doctype is just written <!doctype html>

Example of doctype in HTML 5Edit

<!DOCTYPE html>
<html>
    <head>
    </head>
    <body>
    </body>
</html>

The doctype must always be at the top of the document.

Document without doctypeEdit

Documents without doctype would work in most browsers ,but would not be classified as a valid document.(see Validation).