I am interested to learn class field theory. I want to know whether or not group homology and cohomology are prerequisites for class field theory. One of the answers to this question suggests that one can learn local class field theory without homology and cohomology.
Is it possible to learn global class field theory without homology and cohomology ?
Also, what would be a good book (or lecture note) to study homology and cohomoogy (suitable for beginners) ?
Elementary books on class field theory are Janusz and Childress; see also Garbanati's beautiful article (http://projecteuclid.org/euclid.rmjm/1250128658). For cohomology in a number theoretical context I strongly suggest Weiss (Cohomology of groups).