1 to 1
referring to copies, SS docs to SS copies
1 to 2
referring to copies, SS docs to DS copies
2 to 1
referring to copies, DS docs to SS copies
2 to 2
referring to copies, DS docs to DS copies
4/4
“four over four”: a trade designation for a piece printed with four colors (full color printing) on the front side and four colors (full color printing) on the backside
4C
4 colors - color printing