No, all bananas are not yellow.
While the most common type of banana we see is yellow when ripe, other varieties come in different colors, most notably red. These red bananas, also known as Red Dacca bananas, demonstrate that the popular assumption of bananas being exclusively yellow is incorrect. The color of a banana depends on the variety and its ripeness. Green bananas, which are unripe, are also readily available. The "yellow banana" is, therefore, just one kind of many within the larger banana family.
