Originally Posted by rnd me
think of it like XHTML, there were transitional, frameset, and strict versions.
That's exactly what it is like.
In (X)HTML the strict doctype is there for people using only HTML 4 (or XHTML 1.0). The other two doctypes are for pages that are still transitioning from HTML 3.2 and which still use some of the long obsolete HTML 3.2 tags that were removed from HTML in 1997.
That most web pages still use HTML 3.2 even though HTML 4 has been the standard for over 15 years is because a lot of people do not understand that the transitional doctype is there for web pages that are transitioning from the long dead HTML 3.2 to the new HTML 4 standard.