The difference between a white birthmark and a white spot is as follows.
White birthmarks generally occur mainly in infants and young children shortly after birth, and histopathological examination of white birthmarks can clearly show hypopigmentation or loss of pigmentation. White spots are mainly caused by disease and are a symptomatic manifestation, such as white pityriasis and senile leukoplakia all of which can result in varying degrees of white spots. The two can be further differentiated clinically by histopathological examination.