'Kedu' means 'hello' or how are you and 'o di mma' means 'fine thank you'. Another popular word, ndewo, means 'good day or welcome or good afternoon or evening. People may reply 'oga diri go; meaning 'whatever you wished be with you as well'
The proper greetings words are: Assalamu Aleikom (that means in English Peace be upon you), or Assalamu Aleikom WA Rahmatoh Allah (that means in English Peace and Mercy of Allah be upon you), or...