 GE always adopted the largest and fastest in the Honeywell 6000 family.GE ISBD created a custom connection between Mark II and the original batch operating system for the GE systems, the General Comprehensive Operating System (GCOS).Dubbed the "Foreground/Background Interface (FBI)", it allowed Mark II users to create batch jobs and "submit" them to be sent automatically to a system running GCOS, run there when convenient and the output returned to the Mark II user for review.