The ceremony of wearing the Janeu is known as Upanayana, which marks the beginning of the formal education of a Hindu boy. During the ceremony, the boy is initiated into the Gayatri Mantra and given the Janeu by a priest, who recites mantras and blesses the boy.
The Janeu is worn diagonally across the torso, with one end hanging from the left shoulder and the other end tucked under the right arm. It is considered a sacred thread and is not to be removed except during certain specific rituals or in case of impurity.
While the Janeu is traditionally worn by Hindu males, its practice and significance vary across different regions and communities.