The Human Being
The aesthetic appeal of the human form to other humans is partly biological, partly cultural, and partly individual. First off, as a form of self-affirmation, people tend to have a bias toward others that look like themselves.
The beauty of the human form has 2 main facets: the face and overall body shape. The most attractive faces emphasize features that are biologically appealing.
The face of a strikingly beautiful woman has some combination of larger-than-average eyes, higher-than-average forehead, fuller-than-average lips, shorter-than-average jaw, and smaller-than-average chin and nose. Clear skin, high cheekbones, and lustrous hair complete the picture of beauty. All of these are features of physical health and are indicative of fertile mating material.
Although certain facial characteristics are broadly appealing, people also routinely disagree about the relative attractiveness of faces. This discrepancy owes to personal experience. Faces like those with which we have shared good times are naturally more attractive, as they invoke a sense of pleasant familiarity.