Agni (Sanskrit: अग्नि [ˈɐgni], meaning 'fire'), also called Agni Deva ('fire deity'), is the Hindu god of fire. As the guardian deity of the southeast direction, he is typically found in southeast corners of Hindu temples. In the classical cosmology of Hinduism, fire (Agni) is one of the five inert impermanent elements (Pañcabhūtá) along with sky (Ākāśa), water (Apas), air (Vāyu) and earth (Pṛthvī), the five combining to form the empirically perceived material existence (Prakṛti).
In the Vedas, Agni is a major and most invoked god along with Indra and Soma. Agni is considered the mouth of the gods and goddesses and the medium that conveys offerings to them in a homa (votive ritual). He is conceptualized in ancient Hindu texts to exist at three levels, on earth as fire, in the atmosphere as lightning, and in the sky as the sun. This triple presence accords him as the messenger between the deities and humans in the Vedic scriptures. The relative importance of Agni declined in the post-Vedic era, as he was internalised and his identity evolved to metaphorically represent all transformative energy and knowledge in the Upanishads and later Hindu literature. Agni remains an integral part of Hindu traditions, such as being the central witness of the rite-of-passage ritual in traditional Hindu weddings called Saptapadi (seven steps and mutual vows), in the Upanayana ceremony of rite of passage, as well being part of the diyā (lamp) in festivals such as Deepavali and Arti in Puja.