The final section of Patañjali outlines the yogic concept known as kaivalya. The term means something like liberation or emancipation. In this case, it’s our emancipation from the suffering of the world.
Here, the sutras explain that the goal of yoga is self-knowledge and that by better understanding our own realities we can better understand the universe. It explains how our minds have veils that cover the true nature of things and how yoga practice can remove these veils for us. In the end, this results in kaivalya and with it our freedom from suffering.