Egypt has long been a cultural focus of the Arab world, while remembrance of the rhythms of sub-Saharan Africa, in particular West Africa, was transmitted through the Atlantic slave trade to modern samba, blues, jazz, reggae, rap, and rock and roll. The 1950s through the 1970s saw a conglomeration of these various styles with the popularization of Afrobeat and Highlife music. Modern music of the continent includes the highly complex choral singing of southern Africa and the dance rhythms of soukous, dominated by the music of the Democratic Republic of Congo. Recent developments include the emergence of African hip hop, in particular a form from Senegal blended with traditional mbalax, and Kwaito, a South African variant of house music. Afrikaans music, also found in South Africa, is idiosyncratic being composed mostly of traditional Boer music, while more recent immigrant communities have introduced the music of their homes to the continent.