There is quite a lot of difference. For what White and Black really means are the methods used. White magic we commune with The Divines and the Angels While in Black magic we commune with the devil and the wicked ones. The method used for white magic are unharmful and the working of white magic is of positive flow. They don't backfire and are powerful and very healing. For Black magic there you see, it's all evil intentions and negative energies put into it. It is harmful in its works to get you any result and may backfire easily with other spell casters to reflect it back. In white magic, it doesn't happen that way because the white magic convinces the other that they are not doing anything wrong and making things right in such a way that no one comes to harm. I would suggest while working with black magic, use protection of some sorts so even if it backfires you don't get any harm. But for white magic, It needs its own protection and you can protect it with your belief in it and that it's working for you even when you don't see anything yet happening. White magics are Sure Promises while Black magics are Deals.