An alter ego (Latin, "the other I") is a second self, a second personality or persona within a person. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. The second ( SI symbol s) sometimes abbreviated sec, is the name of a unit of Time, and is the International System of Units The self is a key construct in several schools of Psychology, broadly referring to the cognitive representation of one's identity A persona, in the word's everyday usage is a social Role or a character played by an Actor. The term person is used in Common sense to mean an individual Human being. It was coined in the early nineteenth century when schizophrenia was first described by early psychologists. The 19th century of the Common Era began on January 1, 1801 and ended on December 31, 1900, according to the Gregorian calendar Schizophrenia ( from the Greek roots schizein (σχίζειν "to split" and phrēn 
The term alter ego is commonly used in literature analysis and comparison to describe characters who are psychologically identical, or sometimes to describe a character as an alter ego of the author, a fictional character whose behavior, speech or thoughts intentionally represent those of the author. Literary criticism is the study discussion evaluation and interpretation of Literature. Psychology (from Greek grc ψῡχή psȳkhē, "breath life soul" and grc -λογία -logia) is an Academic and
The characters Doctor Jekyll and Mister Hyde in Robert Louis Stevenson's thriller Strange Case of Dr Jekyll and Mr Hyde represent an exploration of the concept that good and evil exist within one person, constantly at war. Strange Case of Dr Jekyll and Mr Hyde is a Novella written by the Scottish author Robert Louis Stevenson and first published in 1886 Robert Louis Balfour Stevenson (13 November 1850–3 December 1894 was a Scottish novelist poet and travel writer, and a representative of Neo-romanticism in Strange Case of Dr Jekyll and Mr Hyde is a Novella written by the Scottish author Robert Louis Stevenson and first published in 1886 Edward Hyde literally represents the doctor's other self, a psychopathic being unrestrained by the conventions of civilized society, who shares a body with the doctor.
The term and concept also frequently appear in popular fiction, such as in comic books, for the secret identity of a superhero, vigilante, crime fighter or villain. Genre fiction is a term for fictional works ( Novels short stories) written with the intent of fitting into a specific Literary genre A comic book (often shortened to simply comic and sometimes called a comic paper or comic magazine) is a Magazine or Book of narrative A secret identity is an element of fiction wherein a character develops a separate Persona (usually adopting a Pseudonym) while keeping their true identity A superhero (sometimes rendered super-hero or super hero) is a Fictional character "of unprecedented physical prowess dedicated to acts of derring-do A vigilante is a person who ignores Due process of law and enacts their own form of Justice in response to a perception of insufficient response by the Related concepts include avatar, doppelgänger, impersonator, and split personality. Avatar or Avatara (अवतार IAST Avatāra) is often inaccurately translated into English as incarnation A doppelgänger ( or fetch is the ghostly double of a living person a sinister form of Bilocation. An impersonator is someone who imitates or copies the Behavior or actions of another Dissociative Identity Disorder ( DID) as defined by the American Psychiatric Association 's Diagnostic and Statistical Manual of Mental Disorders (DSM