Carl Jung proposed that there are 8 cognitive functions that determine how people perceive and judge information: sensing, intuiting, thinking, and feeling as the four functions, each expressed in an extraverted or introverted orientation. These functions influence how people gather and process information through perception and then make decisions through judgement. The document provides descriptions of each of the 8 functions and their extraverted and introverted expressions. It suggests considering your preferred functions to determine optimal learning strategies.