The explosive first half of a snatch, no catch.
Keep the bar close and brushing your hips, the power is all in the triple extension.
The snatch pull is the full pull of a snatch with the catch deleted, so you can overload the part that produces all the power. The hamstrings do the heavy work, controlling the bar off the floor and loading the hips for the violent triple extension, while the glutes fire to finish the hips through at the top. Weightlifters use it to pull more than they can snatch, and everyone else can steal it as raw posterior-chain power work.
Typically at or above your best snatch, since there is no catch to limit you. If the bar path breaks down or your back rounds, you have gone past useful heavy.
Not deliberately. The arms stay long like ropes while the legs and hips do the work, and any elbow bend at the top should come from the bar floating, not from you pulling with the biceps.
The snatch pull finishes at full extension with a shrug and the bar low. The high pull adds an aggressive arm finish to bring the bar toward the chest. The pull is about extension power, the high pull adds the upper body.
