Could::someone::explain::what's::with::all::those::colons?

From: Greg Shenaut (gkshenaut_at_ucdavis.edu)
Date: 06/22/04 

Date: Tue, 22 Jun 2004 03:57:22 +0000 (UTC)

I notice that a lot of tcl library functions have double colons in
their names, which looks rather baroque. I think it may have
something to do with namespaces, which I haven't delved into yet.
Is there a brief summary of when & why the colons are used that
someone could point me to?

Thanks

Greg Shenaut