This song, a Grammy-award winner for Record of the Year - yes, this song. Not "Africa" - was NOT about Rosanna Arquette, but the band really wanted you to think it was. She was dating a member of the band at the time, but the song wasn't really about her, but about a lot of ex-girlfriends. She just had a nice, melodic name.
The song, like a lot of Toto's work, is heavily jazz influenced, using a lot of structure and meters from that genre not usually seen in pop/rock music. Horns and keyboards sit right alongside guitars, basses, and drums.
By the way, if you look closely, you'll see Patrick Swayze is one of the backup dancers. No joke!