Id: Unconscious thought - selfish and aggressive instincts which demand immediate gratification
Ego: Reality check - balancing demands of the Id and Superego
Superego: Moralistic part of personality which represents the ideal self of who we ought to be

Strengths -
Theory had a large influence on early psychology & western thought
Can be practically applied through psychoanalysis

Studies behaviour that can be observed & measured
Basic processes are the same in all species

Strengths -
Scientifically credible as observations are in highly controlled lab settings and helps for replication
Principles have been applied to real life situations such as token economies

Behaviour is learned through observation and imitation as well as direct and indirect conditioning

Strengths -
A more comprehensive account of learning
Helps explain cultural differences
Less deterministic than behaviourism

Internal mental processes should be studied scientifically and inferences on what is happening should be made indirectly
The mind is like a computer

Strengths -
Lab experiments produce reliable & objective data
Has influenced development of artificial intelligence and machines like robots
Less deterministic than other approaches