Personality is the particular combination of emotional, attitudinal, and behavioral response patterns of an individual. Different personality theorists present their own definitions of the word based on their theoretical positions.[
Beginning of personality study
The study of personality started with Hippocrates‘ four humours and gave rise to four temperaments. The explanation was further refined by his successor Galen during the second century CE. The Four Humours theory held that a person’s personality was based on the balance of bodily humours; yellow bile, black bile, phlegm and blood. Choleric people were characterized as having an excess of yellow bile, making them irascible. High levels of black bile was indicative of melancholy and pessimism. Phlegmatic people were thought to have an excess of phlegm, leading to their sluggish, calm temperament. Finally, people thought to have high levels of blood were said to be sanguine and were characterized by their cheerful, passionate dispositions. 
2B. WHAT ARE THE IMPORTANCE OF PERSONALITY TESTING TO A TEACHER.
A personality test is a questionnaire or other standardized instrument designed to reveal aspects of an individual’s character or psychological makeup. The first personality tests were developed in the early 20th century and were intended to ease the process of personnel selection, particularly in the armed forces. Since these early efforts of these test, a wide variety of personality tests have been developed, notably the Myers Briggs Type Indicator (MBTI), the MMPI, and a number of tests based on the Five Factor Model of personality. Today, personality tests are used in a range of contexts, including individual and relationship counseling, career planning, and employee selection and development.
There are many different types of personality tests(7). The most common type, the self-report inventory, also commonly referred to as objective personality tests, involves the administration of many questions, or “items”, to test-takers who respond by rating the degree to which each item reflects their behaviour, and can be scored objectively. The term item is used because many test questions are not actually questions; they are typically statements on questionnaires that allow respondents to indicate level of agreement (using a Likert scale or, more accurately, a Likert-type scale). A sample item on a personality test, for example, might ask test-takers to rate the degree to which they agree with the statement “I talk to a lot of different people at parties” by using a scale of 1 (“strongly disagree”) to 5 (“strongly agree”). The most widely used objective tests of personality is the Minnesota Multiphasic Personality Inventory (MMPI) which was originally designed to distinguish individuals with different psychological problems. Since then, it has become popular as a means of attempting to identify personality characteristics of people in many every-day settings.  In addition to self-report inventories, there are many other methods for assessing personality, including observational measures, peer-report studies, and projective tests.
SOME OF THE IMPORTANCE OF PERSONALITY TESTING TO A TEACHER CAN BE OUTLINE BELOW;
1. Teachers give tests to discover the learning abilities of their students.
2. It attempts to measure an individual’s personal traits scientifically.
3. Testing, in education and psychology, is an attempt to measure a person’s knowledge, intelligence, or other characteristics in a systematic way.
4. Teachers give tests to discover the learning abilities of their students.
5. They also give tests to see how well students have learned a particular subject.
6. Some teachers gives tests in order to help people choose a vocation, and to help them understand their own personality better.
7. They are important for allowing students to let off steam.
Examples of personality tests
- The first modern personality test was the Woodworth Personal data sheet, which was first used in 1919. It was designed to help the United States Army screen out recruits who might be susceptible to shell shock.
- The Rorschach inkblot test was introduced in 1921 as a way to determine personality by the interpretation of abstract inkblots.
- The Thematic Apperception Test was commissioned by the Office of Strategic Services (O.S.S.) in the 1930s to identify personalities that might be susceptible to being turned by enemy intelligence.
- The Minnesota Multiphasic Personality Inventory was published in 1942 as a way to aid in assessing psychopathology in a clinical setting.
- Myers-Briggs Type Indicator (MBTI) is a psychometric questionnaire designed to measure psychological preferences in how people perceive the world and make decisions. This 16-type indicator test is based on Carl Jung’s Psychological Types, developed during World War II by Isabel Myers and Katherine Briggs.
- Keirsey Temperament Sorter developed by David Keirsey is influenced by Isabel Myers sixteen types and Ernst Kretschmer‘s four types.
- The 16PF Questionnaire (16PF) was developed by Raymond Cattell and his colleagues in the 1940s and 1950s in a search to try to discover the basic traits of human personality using scientific methodology. The test was first published in 1949, and is now in its 5th edition, published in 1994. It is used in a wide variety of settings for individual and marital counseling, career counseling and employee development, in educational settings, and for basic research.
- The Five Factor Personality Inventory – Children (FFPI-C) was developed to measure personality traits in children based upon the Five Factor Model (Big Five personality traits).