The gluteus maximus (also known as glutæus maximus or, collectively with the gluteus medius and minimus, the glutes) is the largest and most superficial of the three gluteal muscles. It makes up a large portion of the shape and appearance of the buttocks.
The buttocks are formed by the masses of the gluteal muscles or 'glutes' (the gluteus maximus muscle and the gluteus medius muscle) superimposed by a layer of fat.