society. When people do not follow the conventional social and moral rules of their society, the behavior is considered to be abnormal. Observer discomfort. If a person's behavior brings discomfort to those in observation, it is likely to be considered abnormal. The standard criteria in psychology and psychiatry is that of mental illness or mental disorder. Determination of abnormality in behavior is based upon medical diagnosis. Other criteria include: Statistical infrequency: statistically rare behaviors are called abnormal. Though not always the case, the presence of abnormal behavior in people is usually rare or statistically unusual. Any specific abnormal behavior may be unusual, but it is not uncommon for people to exhibit some form of prolonged abnormal behavior at some point in their lives. Deviation from social norms: behavior that is deviant from social norms is defined as the departure or deviation of an individual from society's unwritten rules (norms). For example, if one were to witness a person jumping around, nude, on the streets, the person would likely be perceived as abnormal to most people, as they have broken society's norms about wearing clothing. There are also a number of criteria for one to examine before reaching a judgment as to whether someone has deviated from society's norms: Culture; what may be seen as normal in one culture, may be seen as abnormal in another. Situation & context one is placed in; for example, going to the toilet is a normal human act, but going in the middle of a supermarket would be most likely seen as highly abnormal, i.e., defecating or urinating in public is illegal as a misdemeanor act of indecent public conduct. Age; a child at the age of three could get away with taking off clothing in public, but not a person at the age of twenty. Gender: a male responding with behavior normally reacted to as female, and vice versa, is often likely to be seen as abnormal or deviant from social norms. Historical context; standards of normal behavior change in some societies, sometimes very rapidly. Failure to function adequately: behavior that is abnormal. These criteria are necessary to label an abnormality as a disorder, if the individual is unable to cope with the demands of everyday life. Psychologists can disagree on the boundaries that define what is 'functioning' and what is 'adequately', however, as some behaviors that can cause 'failure to function' are not