The primary color of a banana is yellow. This vibrant hue typically signifies ripeness in the context of bananas, making them visually appealing and easily identifiable. When bananas are unripe, they are often green, and as they ripen, they transition to yellow before potentially developing brown spots as they over-ripen. The color yellow in bananas is associated with vitamin C, and their sweet, soft texture contributes to their popularity as a snack.