Tswana, also known by its native name Setswana, is a Bantu language indigenous to Southern Africa and spoken by about 8.2 million people. It is closely related to the Northern Sotho and Southern Sotho languages, as well as the Kgalagadi language and the Lozi language.

Tswana is an official language of South Africa and Zimbabwe. It is a lingua franca in Botswana and parts of South Africa, particularly North West Province. Tswana speaking ethnic groups are found in more than two provinces of South Africa, primarily in the North West, where about four million people speak the language. An urbanised variety is known as Pretoria Sotho, and is the principal unique language of the city of Pretoria. The three South African provinces with the most speakers are Gauteng (circa 11%), Northern Cape, and North West (over 70%). Until 1994, South African Tswana people were notionally citizens of Bophuthatswana, one of the bantustans of the apartheid regime. The Tswana language in the Northwest Province has variations in which it is spoken according to the ethnic groups found in the Tswana culture (Bakgatla, Barolong, Bakwena, Batlhaping, Bahurutshe, Bafokeng, Batlokwa, Bataung, and Batswapong, among others); the written language remains the same. A small number of speakers are also found in Zimbabwe (unknown number) and Namibia (about 10,000 people).

The first European to describe the language was the German traveller Hinrich Lichtenstein, who lived among the Tswana people Batlhaping in 1806 although his work was not published until 1930. He mistakenly regarded Tswana as a dialect of the Xhosa, and the name that he used for the language "Beetjuana" may also have covered the Northern and Southern Sotho languages.

The first major work on Tswana was carried out by the British missionary Robert Moffat, who had also lived among the Batlhaping, and published Bechuana Spelling Book and A Bechuana Catechism in 1826. In the following years, he published several other books of the Bible, and in 1857, he was able to publish a complete translation of the Bible.

The first grammar of Tswana was published in 1833 by the missionary James Archbell although it was modelled on a Xhosa grammar. The first grammar of Tswana which regarded it as a separate language from Xhosa (but still not as a separate language from the Northern and Southern Sotho languages) was published by the French missionary, E. Casalis in 1841. He changed his mind later, and in a publication from 1882, he noted that the Northern and Southern Sotho languages were distinct from Tswana.

Solomon Plaatje, a South African intellectual and linguist, was one of the first writers to extensively write in and about the Tswana language.

The vowel inventory of Tswana can be seen below.

Some dialects have two additional vowels, the close-mid vowels /e/ and /o/. The circumflex on e and o in general Setswana writing is only encouraged at elementary levels of education and not at upper primary or higher; usually these are written without the circumflex.