There are several theories regarding the concept of intelligence proposed by psychologists over time. Carroll proposed a three-stratum model of intelligence focusing on specific, broad, and general cognitive abilities. Gardner theorized multiple intelligences including linguistic, logical-mathematical, musical, bodily-kinesthetic, interpersonal, intrapersonal, naturalistic, and spatial abilities. Sternberg described intelligence as having analytic, creative, and practical components in his triarchic theory. While these theories differ in how they conceptualize intelligence, they have all contributed to the understanding of human intelligence and cognitive abilities.