Originally Posted by Barabaika

I've never used them and I don't get their purpose and advantages.

My simple front brakes on different bikes work pretty nicely. I just tighten the cable adjusters regularly and change the pads every year or so when they wear out.

If you have plastic wheels, then regular brakes don't work well and you have to install heavy hydraulic brakes. Also, modern brake calipers are too short for fenders and bigger tires, so they invented disk brakes.