Spirit Control allows its user to achieve a multitude of potent abilities through their ki, including Instant Transmission (a basic ability), Cloning, Gigantification and Healing (an advanced ability). These abilities achieved through Spirit Control are used by shifting, splitting and growing the user's spirit. Achieving good Spirit Control allows the user to sense ki from a much greater distance and also user to utilize their energy to attack much more efficiently, though at first this newfound ability to use their ki properly causes the power to be somewhat uncontrollable; this was demonstrated by Vegeta, who tried to use a simple finger beam but ended up firing off a powerful energy wave.
After the Frieza Saga, Goku learns Spirit Control from the Yardrats and with it learns how to apply it to use Instant Transmission. Numerous other fighters have obtained the ability to use Spirit Control to utilize Instant Transmission through interaction with Goku.
In the Galactic Patrol Prisoner Saga, Vegeta goes to Yardrat to try and learn Spirit Control. By learning Spirit Control, Vegeta is able to augment his combat abilities, as demonstrated by Vegeta's Galick Beam becoming more powerful after his Spirit Control training.