Where does Jello Come from?

Jell-O (gelatin) is protein molecules that are heated then cooled; during this process particles of water are trapped. Rumors have swirled around saying the protein comes from horses hooves, but that can’t be true, or can it? The protein in Jell-O comes from animal tissue (hide trimmings) that’s rendered and purified. I never thought of Jell-O as a meat!