Igbo (; ; archaically Ibo ) (Igbo: Asụsụ Igbo), is the principal native language of the Igbo people, an ethnic group of southeastern Nigeria. There are approximately 24 million speakers, who live mostly in Nigeria and are primarily of Igbo descent. Igbo is written in the Latin script, which was introduced by British colonialists. There are over 20 Igbo dialects. There is apparently a degree of dialect levelling occurring. A standard literary language was developed in 1972 based on the Owerri (Isuama) and Umuahia (such as Ohuhu) dialects, though it omits the nasalization and aspiration of those varieties. There are related Igboid languages as well that are sometimes considered dialects of Igbo, the most divergent being Ekpeye. Some of these, such as Ika, have separate standard forms. Igbo is also a recognised minority language of Equatorial Guinea.