A woman selling "Rakhis" waits for customers at her roadside stall Wednesday ahead of the Raksha Bandhan festival in Kolkata . (RUPAK DE CHOWDHURI/REUTERS)

The annual festival, also known as “Rakhi”, always falls on a full moon and symbolizes a sister’s love for her brother, and brother’s life-long vow to protect his sister.

On the day of the Raksha Bandhan, a sister ties a decorative thread called “rakhi” on the wrists of her brother. In return, he gives her money, sweets, and other gifts.

See photos of the brilliant colors of Raksha Bandhan below:

An Indian woman looks at a rakhi, a sacred thread tied on the wrist, at a shop ahead of Raksha Bandhan festival in Ahmadabad, India, Wednesday. (Ajit Solanki/AP)