How is simple dog training different from obedience dog training? When I teach my dog to sit, lie down and so on, doesn't it mean I train him to be obedient? I'm confused.
Very simple, The dog may know how to sit lie down roll over whatever, that doesn't mean he will want to do it when his attention is somewhere else. An obedient dog will focus on you and what you are asking of him and do it even with distractions around.
A dog trained in obedience knows the basic commands but may refuse to do them for whatever reason, while an obedient dog will always perform the requested action. Obedience training teaches your dog to be obedient.
Apart from that, training is a more general term that includes obedience training but is not limited with it. There are other types of training as well like agility training, tracking training, police, search, rescue training, etc.