In the outdoor and "EDC" (Everyday Carry) community, "Tri-Zip" (or 3-Zip) refers to a revolutionary system popularized by Mystery Ranch.
Dana Gleason Interview :: The invention of the 3Zip (Part 1) Treszip
It uses the .TRZ extension as an alternative to the standard Newick format, making large datasets easier to share. In the outdoor and "EDC" (Everyday Carry) community,