Which doctype should i use html5

What does it do [duplicate] Ask Question. Asked 10 years, 5 months ago. Active 10 years, 5 months ago. Viewed 87k times. Improve this question. Community Bot 1 1 1 silver badge. Add a comment. Active Oldest Votes. Improve this answer. Kevin Peno Kevin Peno 8, 1 1 gold badge 32 32 silver badges 55 55 bronze badges. Actually, it does determine whether a document is rendered as strict mode, almost strict mode, or quirks mode, so it does serve a purpose.

See this table: hsivonen. The Doctype does two things. It identifies which dialect of HTML you're using. It controls whether the browsers uses "standards" or "quirks" mode to render the document. Will Martin Will Martin 3, 1 1 gold badge 23 23 silver badges 37 37 bronze badges. I don't think a page last edited in , and originally created in is a reliable reference at this point. This means that in many XML languages, doctype declarations are not necessarily useful. The list below is provided only if you actually need to declare a doctype for these types of documents.

The doctype declarations below are valid, but have mostly an historical value — a doctype declaration of a more recent equivalent ought to be used in their stead.

Learn to code for free. Get started. Forum Donate. Three separate rendering modes were generally available across browsers. Full standards mode renders pages according to the W3C web standards. Quirks mode renders pages in a non standards compliant way. Almost standards mode is close to full standards mode, but features support for a small number of quirks.

Usage The Doctype Declaration must be the very first line of code in an HTML document, aside from comments, which can go before it if needed. As I mentioned earlier, the doctype is also used by validators, which you will learn more about later in this article series. For now, all you need to know is that a validator is used to check that the syntax of your HTML document is correct and does not contain any mistakes. The validator programs look at the doctype you have used to determine what rules to use.

So, now that you know that you need to insert a doctype and what it is used for, how will you know which one to choose? You could even create your own if you feel up to something more advanced. Note: "Real" XHTML should be delivered to the web browser as XML, but the details of how and when to do that, and the implications it has, is beyond the scope of this particular article.

Both of these doctypes will ensure that browsers use their Standards mode when dealing with your document. The most noticeable effect that will have on your work is that you will get more consistent results when styling the document with CSS.