Four interrelated qualities distinguish Jewish folk literature: (a) historical depth, (b) continuous interdependence between orality and literacy, (c) national dispersion, and (d) linguistic diversity. In spite of these diverging factors, the folklore of most Jewish communities clearly shares a number of features. The Jews, as a people, maintain a collective memory that extends well into the second millennium BCE. Although literacy undoubtedly figured in the preservation of the Jewish cultural heritage to a great extent, at each period it was complemented by orality. The reciprocal relations between the two thus enlarged the thematic, formal, and social bases of Jewish folklore. The dispersion of the Jews among the nations through forced exiles and natural migrations further expanded the themes and forms of their folklore. In most countries Jews developed new languages in which they spoke, performed, and later wrote down their folklore.