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HTML Treehouse Club: HTML Publish a Story Introduction to Workspaces

Posted by Harish Kosuri
Harish Kosuri
Courses Plus Student 839 Points

What is the purpose of this line in code <!DOCTYPE html>.

Hi everyone I just want to ask why this line <!DOCTYPE html> is added at the starting of the code and there is no ending element for it like header <h> has ending element </h>.

2 Answers

Raluca Dumitru
Raluca Dumitru
14,937 Points
Raluca Dumitru
Raluca Dumitru
14,937 Points

You write this so when the file is parsed(read by the browser), the browser knows which version of html it's used in the file. You find the answer here : https://teamtreehouse.com/library/global-structure-of-an-html-document

Harish Kosuri
Harish Kosuri
Courses Plus Student 839 Points

thank you

Aakash Srivastav
seal-mask
.a{fill-rule:evenodd;}techdegree
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 Points
Aakash Srivastav
.a{fill-rule:evenodd;}techdegree
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,638 Points

The HTML syntax of HTML5 requires a DOCTYPE to be specified to ensure that the browser renders the page in standards mode. The DOCTYPE has no other purpose and is therefore optional for XML. Documents with an XML media type are always handled in standards mode. [DOCTYPE]

The DOCTYPE declaration is <!DOCTYPE html> and is case-insensitive in the HTML syntax. DOCTYPEs from earlier versions of HTML were longer because the HTML language was SGML-based and therefore required a reference to a DTD. With HTML5 this is no longer the case and the DOCTYPE is only needed to enable standards mode for documents written using the HTML syntax. Browsers already do this for <!DOCTYPE html>.
Source- HTML5 differences from HTML4: DOCTYPE