What do the following different terms mean? viz., Bank Credit, Net Bank Credit, Food Credit, Gross Bank Credit

The above terms - one of my friends, who is a banker, used to say. But I could not get a clear meaning / explanation for the above terms. Kindly help me by giving meaning / explanation for the above terms viz., Bank Credit, Gross Bank Credit, Net Bank Credit, Food Credit, Non food credit. As I am a commerce student, I wish to know about these. Please help me. Thank you very much.