The number of simultaneous colours is determined by the number of bits associated with each pixel in the display memory. The more colors, the more bits. If n bits per pixel are used, 2n colour combinations can be generated. EGA uses from 1-4 bits per pixel, permitting up to 16 (24) colours to be displayed on the screen simultaneously. The BGA has an added mode that supports 8 bits per pixel, or 256 (28) simultaneous colors.