I feel like these two issues are related.
I've gotten fairly dangerous with XSL but my ignorance of namespaces means my 
knowledge can only go so far.  I guess it speaks well for XML and XSL that I've 
been so productive without having a deeper knowledge of XML.
I understand the basic idea that the prefix is locally unique to a document, 
and the URI is globally (really globally) unique.  I've seen in books how you 
can declare a namespace in places besides the top of an XML document, but I 
don't know why you would want to.  I know that there are lots of mechanisms for 
manipulating namespaces in XSL but I don't understand why/when to use them.
I'm guessing that I should start with understanding just the XML part, but I 
don't know where to begin.  I know how to use XML when I need one Document type 
for one specific purpose.  I don't understand how or when someone would 
architect a solution that goes beyond that.  For example, I have no idea why I 
would want to or how to go about desinging a solution with multiple, 
interdependent document types.  
I know that XML is a powerful tool, but I feel like I'm not making the most of 
it.
There's so much available out there I was hoping to take advantage of the 
experienced folks on this list.  Any recommendations on articles, websites, 
books welcome.
Thanks,
+jeff
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