Curiosity (from Latin cūriōsitās, from cūriōsus "careful, diligent, curious", akin to cura "care") is a quality related to inquisitive thinking such as exploration, investigation, and learning, evident by observation in humans and other animals. Curiosity is heavily associated with all aspects of human development, in which derives the process of learning and desire to acquire knowledge and skill. The term curiosity can also be used to denote the behavior or emotion of being curious, in regard to the desire to gain knowledge or information. Curiosity as a behavior and emotion is attributed over millennia as the driving force behind not only human development, but developments in science, language, and industry. Causes Curiosity can be seen as an innate quality of many different species. It is common to human beings at all ages from infancy through adulthood, and is easy to observe in many other animal species; these include apes, cats, and rodents. Early definitions cite curiosity as a motivated desire for information. This motivational desire has been said to stem from a passion or an appetite for knowledge, information, and understanding. These traditional ideas of curiosity have recently expanded to look at the difference between perceptual curiosity as the innate exploratory behavior that is present in all animals and epistemic curiosity as the desire for knowledge that is specifically attributed to humans. Daniel Berlyne recognized three major variables playing a role in evoking curiosity; namely, psychophysical variables, ecological variables, and collative variables. Psychophysical variables correspond to physical intensity, while ecological variables to motivational significance and task relevance. Collative variables are called “collative” because they involve a comparison between different stimuli or features, which may be actually perceived or which may be recalled from memory. Berlyne mentioned four collative variables; namely, novelty, complexity, uncertainty, and conflict. At the same time, he suggested that all collative variables probably involve conflict. Additionally, he considered three variables supplementary to novelty, namely change, surprisingness, and incongruity. Finally, curiosity may not only be aroused by the perception of some stimulus associated with the aforementioned variables ("specific exploration"), but also by a lack of stimulation, out of “boredom” ("diversive exploration"). Curiosity-driven behavior Curiosity-driven behavior is often defined as behavior through which knowledge is gained, and should therefore encompass all behaviors that provide access to or increase sensory information. Berlyne divided curiosity-driven behavior into three categories; namely, orienting responses, locomotor exploration, and investigatory responses, or, investigatory manipulation. Previously,