Though the official language of Guinea is French, walk down the street of any town and instead you'll hear Malinke or Susu or any of the other local languages being thrown around. If you ask "Parlez-vous Français?" most people will shake their head non, and will instead (if they speak Malinke) offer some variation of "tana te?" -literally asking "Is there no evil?" The response, of course, is "Tana si te" or "Only peace."
This isn't a question only asked of tubabu or fotés (both mean foreigner in Malinke and Susu, respectively). You'll hear it thrown around constantly, to stranger and friends alike. And the closer you are to a person, the more they will ask you. "Tana te dembaya la? Baara don?" (Is there no evil in your family? In your work?). Always the response: Tana si te. Only peace.
This culture of greeting is so important and often overlooked by visiting westerners. Throughout our Peace Corps training, our formateurs mentioned multiple times that the number one complaint that Guineans had working with Americans was that we don't greet enough. Think back to your last work-related communication (or likely personal communication too). Did you ask how a person was before diving into the reason you called? How about their health? Their family? Their children? For a Guinean, this is just how the conversation goes.
I'm not here to make a value judgement on greeting. Some days I love saying a few words to every person I pass by, and others it absolutly wears me out. But I am here to say this: I love the sincerity that I feel from Guineans when they greet me. I love how welcomed I feel to this country, and I love how kindly everyone treats me. Only peace.