DOCTYPE declarations

…The history of the doctype declaration is a really long and varied one.…I'll give you a link to the details surrounding it a little bit later on.…But for the most part, the doctype is just one of those things…that not everybody understands exactly what it does.…They just know that they need one.…So, what the doctype is supposed to do is tell the browser or…user agent which version of HTML that you'll be using so…it knows which version of the syntax to use in parsing.…But in reality, all it's really doing is triggering something called quirks mode,…which ensures that your page is going to be rendered properly.…

I know this probably sounds confusing, so I just want you to remember this.…You need to have a doctype declaration and…you want the doctype to reflect the version of HTML that you'll be writing.…Now, we're looking at a pretty old document right now.…This was put together in 2002 by the W3C.…I don't believe any of this quality assurance section is…being updated currently, but what this does for…us is it gives us a little bit more of information about the doctype declaration.…