Interest in intelligence and subsequently a method of defining it and quantifying it led to the development of IQ tests or Intelligence tests. An English scientist by the name of Sir Francis Galton was amongst the pioneers in the development of intelligence testing.
He believed that intelligence, like some human traits, was passed down genetically from generation to generation. He then set out to develop an intelligence test. His tests were revolved around sensory perception and reaction in order to determine the level of intelligence. One major setback faced by Galton's test was that scoring well on his test did not indicate that a student would perform well academically, which at that time was considered practical proof of good mental ability. https://free.test-iq.live/