where did all of the different sects come from and why do some pple say bilaal was born a slave and some say he wasn't ... that he became slaves

1) Nabi alaihis salaam mentioned in a Hadith that verily Bani Israail broke up into 72 groups and factions and my ummat will split up into 73 factions, all of them will be in the fire of hell except one group. The Sahaba radiyallahu anhum enquired of which group that was. Nabi alaihis salaam replied that it will be that group who will adopt my sunnat and follow my Sahaba radiyallahu anhum. (Miskaat pg. 30, Qadeemi Kutub Khana, Chapter on holding firm onto the Kitaab and Sunnat).

All those that left aside or rejected the path/group specified in the above hadith broke up into different groups. They either exceeded the bounds in some aspects of Shariat or some totally despised Shariat in action or word and left it out completely. It was also the solemn promise of Shaitaan the accursed after being expelled from Jannat that he would wait in stake to lead the masses astray from the correct path except those sincere servants of Allah Ta'ala upon whom he has no power to beguile and mislead. They would remain steadfast on the guided path and they would never waver off it and these are those concerning whom Nabi alaihis salaam has sounded glad tidings of Jannat for. This is a basic sketch of how different sects came about in Islam. It will almost be impossible to detail the origin of every group presently existent in the world due to the great numbers and in-depth history of their inception.

2) Bilal radiyallahu anhu was born a slave because prior to his birth, his mother was already a slave who belonged to one of the tribes in Makkah Mukarramah. (Usdul Ghaabah by Muhammad bin Hasan Al-Jazri, vol. 1 pg. 237, Darul Ma'rifah).

and Allah Ta'ala Knows Best

Mufti Ebrahim Desai