@Jim: Yes, the question is broad in some sense. I want to know as much as is known for subgroups, in particular, the solvable and abelian subgroups of general linear groups to see whether I can use some of the properties for my applications. @ Mark and Sapir: Thank you for excellent references. Both books are very good. However I think the Suprunenko's book contains more of what I want to know than Wehrfritz's.