information:extraction, stylistic:style_transfer
Writing systems

The earliest evidence of the presence of Islam and literacy goes back to the 14th century. The earliest documented history of the people, traced to the latter part of the 17th century, was in the Yoruba but in the Arabic script called Ajami. This makes Yoruba one of the oldest African languages with an attested history of Ajami (Cf. Mumin & Versteegh 2014; Hofheinz 2018). However, the oldest extant Yoruba Ajami exemplar is a 19th-century Islamic verse (waka) by Badamasi Agbaji (d. 1895- Hunwick 1995). There are several items of Yoruba Ajami in poetry, personal notes, and esoteric knowledge (Cf. Bang 2019). Nevertheless, Yoruba Ajami remained idiosyncratic and not socially diffused, as no standardized orthography existed. The plethora of dialects and the absence of a central promotional institution, among others, are responsible.

In the 17th century, Yoruba was written in the Ajami script, a form of Arabic script. It is still written in the Ajami writing script in some Islamic circles. Standard Yoruba orthography originated in the early work of Church Mission Society missionaries working among the Aku (Yoruba) of Freetown. One of their informants was Crowther, who later would proceed to work on his native language himself. In early grammar primers and translations of portions of the English Bible, Crowther used the Latin alphabet largely without tone markings. The only diacritic used was a dot below certain vowels to signify their open variants and, viz. ⟨ ẹ ⟩ and ⟨ ọ ⟩. Over the years, the orthography was revised to represent tone, among other things. In 1875, the Church Missionary Society (CMS) organized a conference on Yoruba Orthography; the standard devised there was the basis for the orthography of the steady flow of religious and educational literature over the next seventy years.

The current orthography of Yoruba derives from a 1966 report of the Yoruba Orthography Committee, along with Ayọ Bamgboṣe's 1965 Yoruba Orthography, a study of the earlier orthographies and an attempt to bring Yoruba orthography in line with actual speech as much as possible. Still similar to the older orthography, it employs the Latin alphabet modified by the use of the digraph ⟨ gb ⟩ and certain diacritics, including the underdots under the letters ⟨ ẹ ⟩, ⟨ ọ ⟩, and ⟨ ṣ ⟩. Previously, the vertical line had been used to avoid the mark being fully covered by an underline, as in ⟨e̩⟩, ⟨o̩⟩, ⟨s̩⟩; however, that usage is no longer common.

The Latin letters ⟨ c ⟩, ⟨ q ⟩, ⟨ v ⟩, ⟨ x ⟩, ⟨ z ⟩ are not used as part of the official orthography of Standard Yoruba. However, they exist in several Yoruba dialects.

The pronunciation of the letters without diacritics corresponds more or less to their International Phonetic Alphabet equivalents, except for the labial–velar consonant (written ⟨ p ⟩) and (written ⟨ gb ⟩), in which both consonants are pronounced simultaneously rather than sequentially. The diacritic underneath vowels indicates an open vowel, pronounced with the root of the tongue retracted (so ⟨ ẹ ⟩ is pronounced and ⟨ ọ ⟩ is). ⟨ ṣ ⟩ represents a postalveolar consonant like the English ⟨ sh ⟩, ⟨ y ⟩ represents a palatal approximant like English ⟨ y ⟩, and ⟨ j ⟩ a voiced palatal stop, as is common in many African orthographies.

In addition to the underdots, three further diacritics are used on vowels and syllabic nasal consonants to indicate the language's tones: an acute accent ⟨ ´ ⟩ for the high tone, a grave accent ⟨ ` ⟩ for the low tone, and an optional macron ⟨ ¯ ⟩ for the middle tone. These are used in addition to the underdots in ⟨ ẹ ⟩ and ⟨ ọ ⟩. When more than one tone is used in one syllable, the vowel can either be written once for each tone (for example, * ⟨ òó ⟩ for a vowel with tone rising from low to high) or, more rarely in current usage, combined into a single accent. In this case, a caron ⟨ ˇ ⟩ is used for the rising tone (so the previous example would be written ⟨ ǒ ⟩), and a circumflex ⟨ ˆ ⟩ for the falling tone.

In Benin, Yoruba uses a different orthography. The Yoruba alphabet was standardized along with other Benin languages in the National Languages Alphabet by the National Language Commission in 1975, and revised in 1990 and 2008 by the National Center for Applied Linguistics.

In 2011, a Beninese priest-chief by the name of Tolúlàṣẹ Ògúntósìn devised a new script for Yoruba, based on a vision received in his sleep which he believed to have been granted by Oduduwa. This Oduduwa script has also received support from other prominent chiefs in the Yorubaland region of both countries.