Wearing Janeu is popular predominantly among the Brahmins.
The Upanayana ceremony also can be translated as the event that gives the boy an additional sight namely the inner vision with the initiation of Gayatri Mantra
Janeu is made of three stands of cotton thread known as vritas.
Every thread has three cords twining it and a knot. Janeu is associated with a lofty kind of symbolism that enjoins the boy to live an ideal life.