Ardhanarishvara is depicted as half male and half female, split down the middle.
Ardhanarishvara represents the union of masculine and feminine energies of the universe (Purusha and Prakriti) and illustrates how Shakti (the female principle of God) is inseparable from Shiva (the male principle of God). The combined form illustrates the unity of opposites in the universe (non-duality). Both sides are constantly drawn to embrace and fuse with each other. The union of Purusha (Shiva) and Prikriti (Shiva’s energy, Shakti) generates the universe.
Both the Shaktas (devotees of Shakti) and the Shaivas (devotees of Shiva) of the Tantra school of thought believe in the Divine Unity of Shakti with Shiva as the Ultimate Truth.
The right half is male. Often shown holding a trident, his skin is blue in colour and he exudes a certain power and grace that is truly awe-inspiring. The rosary around his neck associates him with asceticism and spirituality. Shiva is the passive force of the universe.
The left half of the body is female. Often shown holding a lotus in Her hand. Her skin is lighter and she appears calm and serene. Her whole being is sensuous and she smiles down kindly on her devotees. Her jewelry associates her with the material illusory world. Shakti is the active force of the universe.