Kalpa
Kalpa (Sanskrit: कल्प kalpa) is a Sanskrit word meaning an aeon, or a relatively long period of time (by human calculation) in Vedic/Puranic cosmology. Generally speaking, a kalpa is the period of time between the creation and recreation of a world or universe. The definition of a kalpa equaling 4.32 billion years is found in the Puranas—specifically Vishnu Purana and Bhagavata Purana.
In Vedas/Puranas, it is equal to 4.32 billion years, a "day of Brahma" or one thousand mahayugas, measuring the duration of the world. Each kalpa is divided into 14 manvantara periods, each lasting 71 yuga cycles (306,720,000 years). Preceding the first and following each manvatara period is a juncture (sandhya) the length of a Satya-yuga (1,728,000) years. Two kalpas constitute a day and night of Brahma. A "month of Brahma" is supposed to contain thirty such days (including nights), or 259.2 billion years. According to the Mahabharata, 12 months of Brahma (=360 days) constitute his year, and 100 such years the life cycle of the universe. Fifty years of Brahma are supposed to have elapsed, and we are now in the shvetavaraha kalpa of the fifty-first; at the end of a kalpa the world is annihilated.
The Matsya Purana (290.3-12) lists the names of 30 kalpas, as follows. These 30 Kalpas constitute 1 month of Brahma: (1) Śveta (2) Nīlalohita (3) Vāmadeva (4) Rathantara (5) Raurava (6) Deva (7) Bṛhat (8) Kandarpa (9) Sadya (10) Iśāna (11) Tamah (12) Sārasvata (13) Udāna (14) Gāruda (15) Kaurma - born of Purnima or full-moon (16) Nārasiṁha (17) Samāna (18) Āgneya (19) Soma (20) Mānasa (21) Tatpurusha (22) Vaikuṇṭha (23) Lakṣmī (24) Sāvitrī (25) Ghora (26) Varāha (27) Vairaja (28) Gaurī (29) Māheśvara - Tripura samhara happended in this Kalpa (30) Pitṛ or Kuhu
The Vayu Purana in chapters 21-25 gives yet another list of 34 kalpas. They are: (1) Bhava (2) Bhuva (3) Tapa (4) Sambhava (5) Rambha (6) Ritu (7) Kratu (8) Vahni (9) Havyavahana (10) Savitra (11) Bhava (12) Ushika (13) Kushika (14) Gandharva (15) Rishabha (16) Shadja (17) Marjaliya (18) Madhyama (19) Vairajaka (20) Nishada (21) Panchama (22) Meghanada (23) Chintaka (24) Akuti (25) Vijnata (26) Mana (27) Bhaava (28) Brihat (29) Shvetalohita (30) Rakta (31) Pitavasasa (32) Sita/Krishna (33) Vishvarupa (34) Shveta