Green card
Green card was the abbreviated name given to the IBM/360 Reference data card that served as the shorthand "bible" for programmers during the late 1960s and 1970s. It rapidly became an icon of the 360 era of programming and was later replaced by the "yellow card" for the IBM/370 product line. The same concept was also later used for an "orange card" for CICS application programming - that showed some internal CICS data structures and their relationships.