Global Polarization Effect and Spin-Orbit Coupling in Strong Interaction

In non-central high energy heavy ion collisions the colliding system posses a huge orbital angular momentum in direction opposite to normal of reaction plane. Due spin-orbit coupling strong interaction, such leads polarization quarks and anti-quarks same direction. This effect, known as global has been recently observed by STAR Collaboration at RHIC that confirms theoretical prediction made more than ten years ago. The discovery attracted much attention on study spin effects collision. It opens new window properties QGP physics -- Spin Physics Heavy Ion Collisions. this chapter, we review original ideas calculations lead predictions. We emphasize role played discuss opportunities challenges connection.