Ethnicity is a way of categorizing a person by means of a shared or presumed ancestry. Unlike race, which is defined according to biological traits, ethnicity is defined according to common origin and other variable characteristics such as language and religion.
According to a group of experts at PBS, ethnicity is a denotation of a group's common ancestry, regardless of race. For example, Hispanic is an ethnicity based on shared Spanish ancestry. People who are ethnically Hispanic may belong to a variety of different races, such as caucasian, black or mestizo.
Often, people identify religion and language with ethnicity. Jewish people, for example, are often considered an ethnicity due to their shared religion, despite the fact that many ethnic Jews have European rather than Israeli ancestry.