The use of dreams to satisfy ungratified needs is referred to as wish fulfillment. This concept was introduced by Sigmund Freud, the founder of psychoanalysis. According to Freud, dreams serve as a way for the unconscious mind to express and fulfill desires that are not being met in waking life. These desires can be related to basic needs such as hunger or thirst, as well as deeper psychological desires or wishes. Freud believed that dreams provided a symbolic representation of these unfulfilled needs, allowing individuals to find satisfaction and release in the dream world.