Ainu culture is the culture of the Ainu people, from around the 13th century (late Kamakura period) to the present. Today, most Ainu people live a life superficially similar to that of mainstream Japanese people, partly due to cultural assimilation. However, while some people conceal or downplay their Ainu identity, Ainu culture is still retained among many groups. The Ainu way of life is called Ainupuri in the Ainu language (literally ainu + puri "customs, manners"). The unique Ainu patterns and oral literature (yukar) have been selected as features of Hokkaido Heritage.