I have been meaning to ask this. What encryption does Whatsapp use? Their FAQ doesn't say. It also doesn't say if it is end-to-end (client-to-client) encrypti

I have been meaning to ask this. What encryption does Whatsapp use? Their FAQ doesn't say. It also doesn't say if it is end-to-end (client-to-client) encryption or if the data is stored in plain on their servers? (I understand it is not stored permanently.)