A pseudonym (/ˈsjuːdənɪm/ sew-də-nim) is a name that a person or group assumes for a particular purpose, which differs from his or her original or true name (orthonym).Pseudonyms include stage names, screen names, pen names, nicknames, aliases, gamer identifications, and regnal names of emperors, popes and other monarchs. Historically they have often taken the form of anagrams, Graecisms, and Latinisations, although there are many other methods of choosing a pseudonym.
Pseudonyms are most usually adopted to hide an individual's real identity, as with writers' pen names, graffiti artists' tags, resistance fighters' or terrorists' noms de guerre, and computer hackers' handles. Actors, musicians, and other performers sometimes use stage names, for example, to mask their ethnic backgrounds. Employers sometimes require employees to use assigned names to help sell products: for example, a company that does business mostly in one country but locates a call center in another country may require its employees to assume names common in the former country to try to draw a more positive or less negative reaction from customers.
In some cases, pseudonyms are adopted because they are part of a cultural or organisational tradition: for example devotional names used by members of some religious institutes, and "cadre names" used by Communist party leaders such as Trotsky and Lenin.
A pseudonym may also be used for purely personal reasons when an individual feels the context and content of the exchange offer no reason, legal or otherwise, to provide their given or legal name.