Language is a system that consists of the development, acquisition, maintenance and use of complex systems of communication, particularly the human ability to do so; and a language is any specific example of such a system.
Literature, most generically, is any body of written works. More restrictively, literature writing is considered to be an art form, or any single writing deemed to have artistic or intellectual value, often due to deploying language in ways that differ from ordinary usage.
That doesn't matter. Don't you give up on this [library] card. Because books can be solid gold. Yeah, the great ones have gotten us through the nights for centuries. Just give a writer an hour to hook you and if he can't wish him the best of luck and find someone else.