Psychology is the science that studies the behavior of organisms
Modern psychology is considered a science because it bases its conclusions on data, information obtained by systematic observations.
Behavior has three aspects:
(1) cognitive processes,
(2) emotional states, and
Cognitive processes refer to what an individual thinks. Emotional states refer to what an individual feels. Actions refer to what an individual does. An organism is any living creature. Consequently, the behavior of dogs, rats, pigeons, and monkeys can be legitimately included in the study of psychology. Such organisms have indeed been subjects in psychology experiments.
traditionally the principal focus of psychology has been humans. When animals
are used in experiments, the implicit goal is often to explore how such basic
processes as learning and motivation, as studied in animals, can cast a light on our
understanding of human behavior