From what I know there is Mandarin, Hokkien, Cantonese But are there other minority dialect? I've heard one spoken outside the mainlands, can anyone confirm?
yeah there are a lot of them: Cantonese is spoken by people around guangdong（广东）area, Hokkien is spoken by people around fujian（福建） area. There are also Mongolian Language spoken by inner mongolian （内蒙古） people, Tibetian Language spoken by tibet （西藏）people. These are the most famous one i believe, there are still a lot of them since china consist of many clan and area. Every clan and area have there own language