well i just started training taekwondo this month. instructors teached us ap chagi, bandal chagi and dollyo chagi. he told us that when doing bandal chagi we should kick the opponent in the waist part and leg rotation should be 45 degrees. and when doing dollyo chagi we should hit the opponent in his chest or even better,his head and leg rotation should be 90 degrees. i did some searching on internet and i found few sites with different explanations, some saying that bandal chagi is actually mostly used for head kicks.also i i am not 100% sure about the rotation thing.does that mean that when you lift your knee to your waist and swing,you should rotate the foot(and the leg ofcourse) 45 or 90 degrees to the left(if you are attacking with you right leg from the outer side) ? and what is actually the biggest difference between bandal and dollyo ? maybe i should ask all this question because i just started training but i really get curious when i am into something. sorry if i didnt explain it properly, english is not my mother language. thanks for the help.