Hi,

I am using Colorbox and other JQuery libraries in my project.

Doctype is important for JQuery library like Colorbox.

I want to know importance and why we need doctype in document.

Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

-Thanks
Zohaib.