Indra (Devanagari: इन्द्र) or Śakra is the leader of the Devas or gods and Lord of Svargaloka or heaven in Hindu mythology. He is the God of war, the god of thunderstorms. His weapon is the bolt (vajra). Indra is one of the chief deities in the Rigveda. He is the twin brother of Agni and hence said to be born of Dyaus Pitar (Father Heaven) and Prithvi Mata (Mother Earth). He is also mentioned as an Aditya, a son of Aditi. His home is situated on Mount Meru.
He has many epithets, notably vṛṣan the bull, and vṛtrahan, slayer of Vṛtra, meghavahana "the one who rides the clouds" & Devapati "the lord of gods or devas". Indra appears as the name of an arch-demon in the Zoroastrian religion, while his epithet Verethragna appears as a god of victory. Indra is also called Śakra frequently in the Vedas and in Buddhism (Pali: Sakka). He is known in Burmese as သိကြားမင်း, ; in Thai as พระอินทร์ Phra In, in Malay as Indera, in Tamil as Intiran, in Chinese as 帝释天 Dìshìtiān, and in Japanese as 帝釈天 Taishakuten.
He is celebrated as a demiurge who pushes up the sky, releases dawn (Ushas) from the Vala cave, and slays Vṛtra; both latter actions are central to the Soma sacrifice. He is associated with Vajrapani - the Chief Dharmapala or Defender and Protector of the Buddha, Dharma and Sangha who embodies the power of all primordial or Dhyani Buddhas. On the other hand, he also commits many kinds of mischief (kilbiṣa) for which he is sometimes punished. In Puranic mythology, Indra is bestowed with a heroic and almost brash and amorous character at times, even as his reputation and role diminished in later Hinduism with the rise of the Trimurti.
Read more about Indra: Origins, In The Rig Veda, In Buddhism, Jainism, Taoism and Bali