estraneo

thumb|The 1919 book, The Stranger, is one of many works of fiction revolving around circumstances following the arrival of a stranger in the lives of established characters.A stranger is a person who is unknown or unfamiliar to another person or group. Because of this unknown status or unfamiliarity, a stranger may be perceived as a threat until their identity and character can be ascertained. Different classes of strangers have been identified for social science purposes, and the tendency for strangers and foreigners to overlap has been examined.