How a standard version of the east African language was formed—and spread across the world

Kiswahili originated in east Africa, spreading around the continent and the globe. It's been adopted as a working language at the African Union and there's a push for it to become Africa's lingua franca or common language. Morgan J. Robinson is a historian of east Africa with a research focus on language who has published a book on Kiswahili called "A Language for the World." We asked her how today's accepted standard version of Kiswahili came into being.