Simple pulley: No force/distance trade- off, only directional
change. Cables may travel through multiple stationary pulleys
and will still offer no force/distance trade-off.
Compound pulley: Load (R) moves half distance cable is pulled
so the effort (F) is halved. Opposite end of cable is stationary
so compound pulley rotates and travels upward with load.
Split pulley: When both cables are pulled simultaneously, load
is distributed equally between each side (lower pulley does not
rotate and load is moved full height). When only one cable is
pulled while the opposite cable is anchored, the split pulley
acts as a compound pulley.