Han's Eysenck proposed a theory of personality named as Eysenck's Theory of Personality. Han's Eysenck described personality as a hierarchy of traits. Eysenck's Theory of Personality (EPQ) measures four dimensions of personality, E - Extraversion/Introversion, N - Neuroticism/Stability, P - Psychoticism/Socialization and with the addition of L - Lie/Social Desirability. Eysenck's Theory of Personality states that each personality is characterized by certain traits: People who lie on the scale of Extraversion are commonly seen as sociable and tends to be carefree, optimistic and impulsive while on the scale of Introversion people are generally quiet and reserved and tends to be serious and reliable. People who lie on the scale of Neuroticism are characterized by instability, anxiety and nervousness while on the scale of stability people are mostly stable, less reactive to stressful situation and preferably calm and level headed. People who lie on the scale of Psychoticism are seen as aggressive, troublesome and lacks empathy while on the scale of Socialization people are generally calm, thoughtful and has a great amount of ability to command one's behavior and restrain impulses. People on the Lie scales are measured on the basis of Social Desirability i.e. up to what extend one's behaviors are socially desirable. Eysenck's two dimensions of personality: Extraversion/Introversion and Neuroticism/Stability further defines four quadrants: High N and high E = Choleric type (unstable extravert): qualities such as - touchy, restless, excitable, changeable, impulsive, irresponsible. High N and low E = Melancholic type (unstable introvert): qualities such as - quiet, reserved, pessimistic, sober, rigid, anxious, and moody Low N and high E = Sanguine type (stable extravert): qualities such as - outgoing, talkative, responsive, easygoing, lively, carefree, leadership). Low N and low E = Phlegmatic type (stable introvert): qualities such as - calm, even-tempered, reliable, controlled, peaceful, thoughtful, careful, and passive. Eysenck's Theory of Personality has proven to be useful for numerous applications such as Career Counselling and Human Resource Management.