What is Chicago blues?

Chicago blues is rhythm guitar based electric guitar blues where the organ, horn section and electric bass guitar are omitted in favor of the electric rhythm guitar because they're not playing in concert venues but rather in clubs, rooms, etc In properly formatted electric guitar blues the song should be carried by an organ, and a horn section and electric bass guitar should be included as in BB King's music It's a little off the reservation It's notable that Albert Collins used a rhythm guitarist backing at least sometimes