Mayo, known natively as Yorem Noki, is an Uto-Aztecan language. It is spoken by about 40,000 of the Mayo (Yoreme) people, who live in the southern portion of the Mexican state of Sonora and in the north of the neighboring state of Sinaloa. Under the General Law on the Linguistic Rights of Indigenous Peoples, it is recognized as a "national language" along with 63 other indigenous languages and Spanish which all have the same validity in Mexico. The language is considered 'critically endangered' by UNESCO.