( the short version) The Pride of 1of the Heavenly Host, who started a rebellion against Creator GOD and thought that since He was tasked with the building of the Thone of Creator GOD, HE (Semyaza, who became lucifer/satan/ baal, moloch etc etcetc) wanted to erect a throne for himself & place it higher that Creator GOD. (what a dipstick) and then He convinced others to rebel against Creator GOD as well. THEY were thrown down out of Heaven. The children of are the Nephilim. Read the book of Enoch. Enoch was tasked with writing the account, to relay the info to his own children. (Enoch's a great teacher) :)