can someone please tell me the main differences between fuzz, distortion, and overdrive so that i know what to get,

i know what fuzz is , and that is what im going to buy, but what are the others and the differences
distortion is typically heavier sounding and is more hard-edged, overdrive is smoother and more natural sounding
"A musician should not be measured by the skill at which they perform, but the passion, and love for music with which they are playing."