Pralaya (Sanskrit: प्रलय, romanized: Pralaya, lit. 'Destruction') is a concept in Hindu eschatology. Generally referring to four different phenomena, it is most commonly used to indicate the event of the dissolution of the entire universe that follows a kalpa (a period of 4.32 billion years) called the Brahmapralaya.
Pralaya also refers to Nityapralaya, the continuous destruction of all animate and inanimate beings that occurs on a daily basis, Prakritapralaya, the great flood produced by Prakriti (Nature) that ends all of creation after the completion of 1,000 Chaturyuga (four-age) cycles, and Atyantikapralaya, the dissolution of one's Atman (Self) due to its union with Brahman (Ultimate Reality). A concept that has been referenced in literature since the Upanishads, the concept of pralaya has been widely discussed in Hindu cosmology as well as philosophy.