difference between intranet and internet crawling

Hi

There are are several posts about the difference between

regex-urlfilter.txt crawl-urlfilter.txt

e.g.http://www.mai
l-archive.com/nutch-userlucene.apache.org/msg06318.html

or 
http://mail-a
rchives.apache.org/mod_mbox/lucene-nutch-user/200503.mbox/%3
c1815d86605033100396d330bemail.gmail.com%3e

but it might stupid, but  what do you mean by intranet and
internet 
crawling?

In the end both of them are just URLs ... right? It seems to
me I 
completely misunderstand something.

Thanks for a hint

Michi

-- 
Michael Wechner
Wyona      -   Open Source Content Management   -    Apache
Lenya
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