1. The POTTU is considered as a religious mark and invokes a feeling of sanctity in the wearer and others. It may vary in color. 2. The POTTU served as an identification of which caste anyone belonged & their profession (based on the colour or varna). Brahmin with a white chandan mark signified purity, as his profession was of a priestly or academic nature. Kshatriya applied red kumkum mark signifying valour and belonged to warrior races. Vaishya wore yellow kesar or turmeric mark signifying prosperity and was a businessman or trader. Sudra applied a black bhasma, kasturi or charcoal mark signifying service as he supported the work of other three divisions. Vishnu worshippers apply a chandan tilak of U shape; Shiva worshippers apply a tripundra of bhasma Devi worshippers a red dot of kumkum..... 3. The spot between the eyebrows is supposed to be the seat of memory & thinking & is known as the Aajna Chakra in Yoga language. The tilak is thus a blessing of the Lord and protection against wrong tendencies and forces. 4. The POTTU or TILAK is suppose to cool the forehead & protect us and prevents energy loss. sometimes the entire forehead is covered with chandan or bhasma. 5. A more recent school of thought from my husbands's senior consultant at Australia was that INDIA GAVE THE WORLD THE NUMBER ZERO, without which there would be no mathmatics, calculations, business or economics. So, Indians proudly show the world on their forehead a round tilak. 6. A mischivous argument is that the red kumkum signifies that a lady is now taken by somebody, and others should be wary of approaching her- danger signal boldly depicting that she belongs to someone. 7. What are your comments ?????