Hi,

SC or scheduled caste, SC or scheduled tribes and OBC or other backward classes are categories who have certain percentages in every college of competitive exams reserved for them which is mainly done to help the disadvantages who are not able to afford the education by subsiding their cost and giving them opportunity to be at parties with other category students. Open category refers to those who have no bar with respect to caste or social status and anyone can apply in that position be it general or SC/ST/OBC.