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Juan Guillermo Mariño
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Juan Guillermo Mariño
Front End Web Development Techdegree Graduate 19,423 Points

Is it really necesary to always put the <!DOCTYPE html> element?

I understood that the <!DOCTYPE html> tag must always be the first thing on the page and always be at the top so the browser can understand what kind of content to expect in the page. Is it really that necesary ALL THE TIME?

2 Answers

Doug Swift
Doug Swift
7,803 Points

It is necessary if you are working with HTML and especially HTML5 so the Browser renders the page in Standards mode. Without it, the browser is forced to render in quarks mode. The DOCTYPE has no other purpose and is therefore optional for XML because documents with an XML media type are always handled in standards mode.

it is an instruction to the web browser about what version of the markup language the page is written in. The doctype declaration refers to a Document Type Definition dtd.