I'm new to github. When I go to download it ("Downloads" tab at github) and click "latest" "tgz"; why do I get "petdance-ack-$extremely_long_number.tar.gz" inst

I'm new to github. When I go to download it ("Downloads" tab at github) and click "latest" "tgz"; why do I get "petdance-ack-$extremely_long_number.tar.gz" instead of "ack-1.9.0.tar.gz"? Same thing happens if I click the curvy-cornered "download" button with the little green downward-pointing arrow.