Most people who speak Swahili speak it as a second language. This process - when the majority of speakers of a language are non-native - tends to simplify a language. For example, Swahili has a much simpler set of sounds than most other Bantu languages, many of which are tonal (Swahili is not tonal), and many of which have three or four way contrasts in their stop consonants (Swahili has two), and some of which have click consonants (Swahili has few "unusual" sounds).