I don't know who really knows what it is. But after having some very strange experience I believe there is in this world many other kinds of life some from a different dimension who can enter our dimension and affect it in the positive or negative way. What are they? I really don't know but yes in the Bible, the Qu'ran and other they speak about it but difficult to be sure of what it is. They talk about it but even when reading between the lines it still not clear and when it happens to us we really don't know what to do, especially in modern society. In Africa and Asia people still have some ancient knowledge and this knowledge is useful like in my case. Thank you.