need a hand fully grasping the concept of 4-link

[thoroughbred rebel]

hey everyone i have been looking at lifting my truck and prices are out of this world for lifts even for basic spring lifts. so for ride quality i have decided to go air ride with a 4-link suspension and bags should be able to build and i mean by hand in my barn one off custom. anywho before i attempt this i am a little confused on how the 4-link works as far as through the swing of the axle and doesnt bind the driveshafts? next is panhard bars what is it? what does it do? thanks everyone.