1) Why do we light a lamp?

Light symbolizes knowledge, and darkness - ignorance. Hence by lighting a Lamp, you remove the Ignorance around you!

2) Why do we do Namaste?

The life force, the divinity, the Self or the Lord in me is the same in all. Recognizing this oneness with the meeting of the palms, we salute with head bowed the Divinity in the person we meet

3)Why do we wear marks (tilak) on the forehead?

The tilak cover the spot between the eyebrows, which is the seat of memory and thinking. It is known as the Aajna Chakra in the language of Yoga! This is also known as the Third Eye of "Enlightenment". This is also known as the "third eye" of 'Mahesha (or Siva)'. The tilak and pottu cools the forehead, protects us and prevents energy loss.

4) Why do we apply the holy ash?

This is known as Viboothi. This is applied on your forhead to remind you that, the "Perishable" body you are in woulkd be turn into ash or dust. When applied with a red dot (kunkumam) at the center, the mark symbolizes Shiva-Shakti (the unity of energy and matter that creates the entire seen and unseen universe). We worship the three-eyed Lord Shiva who nourishes and spread fragrance in our lives. May He free us from the shackles of sorrow, change and death – effortlessly,