Psychology
According to "the Father of Psychoanalysis," dreams are expressions of unconscious wishes, usually wishes of a sexual or aggressive nature. Dreams provide the individual with a safe scenario in which to act out wish-fulfillment, especially when the wish represents a taboo activity. If considerable guilt surrounds the desire then the dream could be wrought with anxiety and turn into a nightmare.
While not all dreams can be categorized this way, some certainly are. For example, I have had two types of dreams that are obviously expressions of unconscious wishes. One type represents the biological wish or need to eat. After going grocery shopping and resisting certain foods because of price or because they are unhealthy foods, I often dream about eating those foods that night.
Another wish-fulfilling dream represents an emotional or psychological state. When I am upset with someone and haven't been able to tell them, I have had dreams in which I am getting angry and enter into arguments with that person. Sometimes in the dream, it's not really that person but rather someone why symbolizes or represents that person, but I know based on the way I feel in the dream that the emotions correspond to the actual individual I dealt with in waking life.
2. The following is a learning scenario using operant conditioning. A girl is mad at her boyfriend because he doesn't do the dishes enough. The boyfriend is the learner, and the behavior that needs to be learned is doing the dishes. Using operant conditioning, the girlfriend can teach the boyfriend to participate more in household chores by either withholding sex from the boyfriend (punishment); yelling at him (negative reinforcement); or being extra nice to him when he does do the dishes (positive reinforcement).
3. Mnemonic devices are one of the best ways to improve memory in certain situations. One way a person could apply mnemonic devices is to try to memorize people's names, something that can be hard to do at a party. So if a woman's name is Meg and has blonde hair, the person can remember her name by associating it with Meg Ryan. Or if a guy has long hair and his name is Jerry the person can use the mnemonic device "Hairy Jerry."
