Swahili is a Bantu language widely spoken in East Africa. It is spoken as a first language by about 5 million people and also serves as a lingua franca across East Africa, where it is spoken by over 30 million people as a second language.
Swahili arose as a complex hybrid of Bantu language and Arabic and spread due to intense trade, including in slaves, between the Arab peninsula and eastern Africa.
An aspect of Swahili and other Bantu languages that may be surprising to speakers of English and other European languages is that grammatical markers (such as pluralization), are often prefixes rather than suffixes. Thus "kitu" means "man", while "vitu" means "men".