Additionally, it is believed that IQ is very little changed during our life and more or less stabilized at the age of 16, although might slightly increase until the age of 30. That means that IQ is not an absolute score but a relative one. In order to determine IQ, people need to take an IQ test with questions about logic, comparison, arithmetic, memory, general knowledge, calculation, logic puzzles and then compare the ratio of the score they achieved with an average score of different age groups achieved. Although IQ became synonyms for intelligence, they are not identical but an IQ is only an estimation of intelligence, mainly due to the abstract nature of the concept of intelligence. The term 'IQ' was coined by the german psychologist William Stern for the German term Intelligenzquotient, his term for a scoring method for intelligence tests at University of Breslau in 1912 book. The sum of the IQ represents the total score derived from a set of standardized tests. IQ, or 'intelligent Quotient' is a psychological measure of rating human intelligence.
