Aptitude refers to innate abilities and potential that allow individuals to excel in certain areas or talents. It represents a person's capability to acquire specific skills or knowledge with training. Aptitudes have several characteristics - they are influenced by both heredity and environment, provide insights into future performance, and can be seen in individual performance. There are various types of aptitude tests that measure abilities in areas like verbal, numerical, and spatial reasoning skills. Common educational aptitude tests include the SAT and DAT which assess skills and overall academic competency.