Śakra (Sanskrit) or Sakka (Pāli) is the ruler of the Trāyastriṃśa Heaven in Buddhist cosmology. His full title is Śakro devānām indraḥ (Pāli: Sakko devānaṃ indo "Śakra, lord of the devas"). In Buddhist texts Śakra is the proper name and not an epithet of this deity; conversely, indra in Sankrit and inda Pali are sometimes used as an epithet for Śakra as "lord". In the Chinese tradition, he is usually analogous with the Taoist Jade Emperor, whose birthday is celebrated on the ninth day of the first lunar month of the Chinese calendar (usually in February).