A test can be defined as an instrument, tool, or procedure that is used to obtain information about a particular outcome. Other definitions include reference to its capacity to measure specific variables and including standardized procedures to gather data on underlying constructs for drawing conclusions or developing hypotheses for further examination. Currently, there are thousands of available tests in many different areas, such as achievement, intelligence, personality, aptitude, and vocational. This entry discusses the various types of test and scores obtained and the psychometric properties of tests.