Intelligence testing is a form of psychological testing of an individual's capacity to learn and deal effectively with his/her environment. IQ (intelligence quotient) is the score of an intelligence test.The Wechsler Adult Intelligence Scale is the most widely used individually administered intelligence test (IQ test) for adults. It comprises of 11 subtests made up of six verbal subtests and five performance subtests. It yields three IQ (intelligence quotient) scores: Verbal Scale IQ, Performance Scale IQ, and Full Scale IQ. A scale for children ages 5 through 15 years is called WISC -- Wechsler Intelligence Scale for Children and a scale for children ages 4 to 6* years is called WPPSI--Wechsler Preschool and Primary Scale of Intelligence.    Classification of Intelligence according to IQ scores     Classification IQ Range Profound mental retardation (MR)    below 20 or 25     Severe MR 20-25 to 35-40 Moderate MR 35-40 to 50-55 Mild MR 50-55 to about 70    Borderline 70-79 Dull normal 80 to 90 Normal 90 to 110 Bright normal 110 to 120 Superior 120 to 130 Very superior 130 and above Source: Diagnostic and Statistical Manual of Mental Disorders (DSM-IV)