Shakti is the primordial cosmic energy of Hinduism, the dynamic divine feminine, the active power that moves through and animates the whole universe. The Sanskrit word means simply power or ability, and as a theological principle it names the force by which anything acts, exists or changes: without shakti, being is inert. In the philosophy of the goddess-centred traditions (Shaktism), this power is understood as feminine and as ultimate, and it is inseparable from the consciousness it activates.
A famous saying captures the relationship: Shiva without Shakti is shava, a corpse, that is, pure consciousness without its energy is motionless and lifeless; it is Shakti that gives it the capacity to create, sustain and dissolve. Every god has his shakti, personified as his consort, and the many goddesses of Hinduism, Parvati, Lakshmi, Saraswati, Durga, Kali, are understood in this framework as forms of the one Shakti, the Mahadevi or Great Goddess.
In the Shakta traditions this feminine power is not subordinate to a male god but is herself the supreme reality, worshipped as the mother of the universe. Shakti is also a term of yogic practice, where it names the coiled energy (kundalini) latent within the body, to be awakened and raised. At its widest, Shakti is the Hindu name for the truth that reality is not static but a living, moving power, and that this power is to be revered as the Goddess.