The sexual curiosity of adolescents can take multiple forms. Youth in the age range of 13 to 16 undergo a complete metamorphosis of their bodies, which extends over a span of several years, and does not unfold at the same speed and in the same sequence for everyone. Hence their desire, shared by a significant number among them, to compare their personal physical and genital development to that of other adolescents. The main subjects of this curiosity are size of penis and amount of pubic hair, topics which predominate over other objects of curiosity in all the « boys’ puberty forums » of all the adolescent websites, and which I will address in a forthcoming chapter on puberty. The perusal of the results of the various questionnaires posted on line by the many adolescent websites shows that large numbers of boys between the ages of 13 and 16 acknowledge having already satisfied this curiosity which consists in wanting to compare the size of their own penis with that of one or several of their fellows. A compilation of surveys carried out by the three websites, Govteen, Vteen and StudentCenter and set out in Table #4 shows that this form of curiosity is anything but the exclusive concern of homosexual or bisexual boys.