Info on KIF language?

Hi all,

I've encountered my first KIF file, a text file, which I think is a
programming language.
The URL is for my downloaded file is:
http://cvs.sourceforge.net/viewcvs.py/sigmakee/KBs/elements.kif?rev=1.3

After searching the 'net, I can find nothing telling me how to use KIF, or
if it can be compiled, etc.

Help would be appreciated.

Thanks!
Dugie

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