Super summary time

Basic differences and why they matter-

stylus cut: This is the shape of the little diamond itself. dofferent cuts have create different quality of music due to their ability to better follow the groove. More expensive cartridges tend to have more esoteric cuts

stylus bonding: The stylus is the tiny diamond at the end of your needle. On a standard "bonded" stylus the majory of what you see is actually a little steel cone which is glued to the needle. At the end of this cone a super tiny diamond is glued on. A "nude" stylus just has a diamond glued to the end of the needle. No metal cone. This is a bonus because it's lighter. Stylus mass is king because the stylus is vibrating up and down super fast and mass at the end of the needle creates momentum, making it more difficult for the needle to go up and down fast enough to follow the bumps perfectly. A "square shank nude" is the next level in nudeness- instead of being glued on to the end of the needle, a tiny hole is cut through the needle and the diamond is crammed into the hole. Less mass etc

cantilever material. The cantilever is thte "needle". The vast majority are made out of an aluminium tube. More expensive needles will use a "tapered cantilever", in which the tube gets thinner as it goes towards the diamond. This reduces resonances. Less resonance = better groove following. Cantilevers can also be made out of more esoteric materials such as boron. These are stiffer (see: resonances) and lighter (see: stylus mass)

fancy sciency stuff also goes on inside the cartridge bodies themselves but... I dunno about that.

Specs:

frequency response- obviously means what frequency range it can produce. I ignore this spec

compliance: this is basically a measure of hot "springy" the needle on the cartridge is. This is important when you get serious about matching the cartridge to your turntable. Basically, if you have a light tonearm, you need a cartridge that's springy,. or the stiff needle will vibrate the light arm too much. If you've got a tpnearm that'd high mass you want a stuff cartridge because..... ok, I dunno.

output: literally how many vikts it creates. potentially important to know if you're picky about gear. If you have a setup with low gain, you'll need high output to be loud enough.

Impedence: Not really important unless you're doing MC cartridges.

MC cartridges and MM cartridges.... it's midnight sorry, someone else can elaborate!