super-duper 0 Light Poster

Hi,

I am trying to learn some XML. I am getting confused, or should I say, getting lost while trying to understand the DTD, SCHEMA, PCDATA and CDATA.

Can someone, please, explain them the simpler way...if there is any? :) I think I am having hard time understanding especially the PCDATA and CDATA. What is the point of having them? How do they work?

Thanks in advance.