The Tay language is a member of the Tai-Kadai language family, primarily spoken in parts of Vietnam and China. It is used by the Tay people, one of the largest ethnic groups in northern Vietnam, and has several dialects that vary by region. Tay is written using the Latin alphabet, which was adapted during the colonial period. The language features tones, which are essential for distinguishing meaning between words. Efforts are ongoing to preserve and promote the Tay language, especially among younger generations, as globalization poses challenges to its use.