Line art, or line drawings, refers to single-color diagrams or drawings consisting of only Black is the fourth color in the process of four-color printing. The "K" in CMYK. Black adds tonal d... More and white with no A grayscale image has no color hues but contains a range of gray levels between pure black or white.... More information. Line art is best reproduced as Vector is a graphic format that does not contain pixels. It is created from mathematical equations a... More graphics.