You’ve got a lot of catching up to do! I too never even had a cassette hub until sometime in the 90’s when I got a second hand Saint Tropez road bike with Shimano 105 6 speed freehub Uniglide drivetrain.

Sorry but I can’t offer a link that shows the full evolution of Shimano’s freehubs over the years. I will say that the continual development and product cycles that favor innovation, have led to a lot of cast off variants that a few of us are passionate about and a few people despise.

I paid particular attention when Uniglide (UG) became Interactive Glide (IG) which then became Hyperglide (HG). Older 6/7 speed frameowners who wanted to fully optimize their frames with the best functioning geartrains had to make a decision -should they spread their frame to 130 to permit 8/9/9 or 11 speed? Or, would they dig their heels in and stockpile a healthy supply of 7 speed parts? I must confess that I’m in the latter category. My Dura Ace 7400 Uniglide 7 speed hub commuter bike has one of the most durable cassette systems imaginable. Unfortunately they are not “future proof” due to the design of the freehub body itself. Yes, you can hunt for a 7403 Dura Ace freehub convertible freehub body which will permit a person to run both 8/9/or 10 speed HG cassettes (the modern HG lockring type) or 7/8 speed UG cassettes (the threaded outer cog type).

The supply of NOS Uniglide parts is finite, since they have been out of production since the early 90’s. Personally, I keep hoping that an ambitious machinist or designer with the latest 3D printer will make some production runs on desirable Uniglide cassette assemblies. The originals, while heavy by modern standards are iconic and collectible as far as I can tell. Modern parts have moved on and are lighter and even better functionally but the build quality and level of polish/or hand-crafted quality of some of these iconic older bits have yet to be matched. Just look at drillium-dude’s work on Imgur if you want to be inspired.