I'll be honest and say this means nothing to me - do you have a link to somewhere I can get more info on that?
(Assuming that you are asking what he means by high bar position)
There's a range of places on your back that you could place the bar doing squats. If your bar rests on the top of your traps, most would consider that a high bar squat. This is in contrast to a bar placement where the bar is more towards the bottom part of your delts. While both bar positions are valid, the lower bar position will put your weight farther back on your heels - something that some lifters have a problem doing otherwise.