HTML <!DOCTYPE>query_builder | Christopher Pisani
Why use <!DOCTYPE html>
When DOCTYPE is declared, the browser will know, what code language you are using, to start parsing the data supplied.
When DOCTYPE is not declared, although it LOOKS like it still works, the browser falls in what is known as the quirks mode. This means that the browser will run in a backward compatibility mode, to render the document designed for old web browsers instead of strictly complying with W3C and IETF standards in standards mode. It will most often, show significantly different results, especially from different browsers.
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