TECHNOLOGY: Suspension Assembly Primer

[GIANT]

...The suspension must provide a force on the slider in a direction into the disk to counteract the upward aerodynamic forces of the air bearing that cause the slider to "take off" from the disk surface. This force must act precisely in the proper location or a twisting force (torque) will be imparted to the slider. Any torque to the slider will cause one of its corners to be too close and the other too far from the disk surface...

http://www.htch.com/primer.asp