~what is the difference between keeping a doctype at the top level and a xmlns schema definition at the top attribute level?

~ how can we achieve auto complete by providing the schema in eclipse? is the auto complete feature something to do with the schema definition itself?.

what is the difference between encoding of type ISO-8859-1 and UTF-8? What is unicode.

What does png, gif, jpeg stand for – what is the difference between these image files?