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HTML Treehouse Club: HTML Publish a Story Comments and Doctype

I Still Don't Know Why You Have to Do <DOCTYPE! html>?

If You Know Please Help(Also, If You Know Where The Instructors get The Stickers They Put on There computers,please tell me)

Ken Alger
Ken Alger
Treehouse Teacher

Jack;

While not all of the stickers are available, a great place to look is at devswag.com for similarly related items.

Happy coding and welcome to Treehouse!

Ken

3 Answers

Stone Preston
Stone Preston
42,016 Points

from the W3

Why specify a doctype? Because it defines which version of (X)HTML your document is actually using, and this is a critical piece of information needed by some tools processing the document.

For example, specifying the doctype of your document allows you to use tools such as the Markup Validator to check the syntax of your (X)HTML. Such tools won't be able to work if they do not know what kind of document you are using.

But the most important thing is that with most families of browsers, a doctype declaration will make a lot of guessing unnecessary, and will thus trigger a "standard" rendering mode.

You declare <DOCTYPE! html> at the top of your html page so that the browser knows how to parse the codes/tags.

This particular declaration is the formal declaration to let the browser know that you are using HTML5 syntax in your code. The browser companies agreed that the word "html" means HTML5.

In the past, you declare the actual HTML version (like html4 / html3 ... or something like that).

I guess from now on, "html" mean the latest html version that the browser can handle.

As to why you have to declare html? because the browser can also display other types of documents such as JSON/txt/...

Thanks

Thanks Ken, Stone Preston, and haunguyen