Wikipedia
According to the Jain cosmology, the śalākāpuruṣa "illustrious or worthy persons" are 63 illustrious beings who appear during each half-time cycle. They are also known as the trīṣaṣṭiśalākāpuruṣa (63 illustrious persons). The Jain universal or legendary history is a compilation of the deeds of these illustrious persons. There life stories are said to be most inspiring.
The śalākāpuruṣa comprise 24 Tirthankaras (Teaching Gods), twelve Chakravartin (universal monarchs, emperors of six continents), nine Balabhadras (gentle heroes), nine Narayanas (warrior heroes) and nine Prati-narayanas (anti-heroes). According to Jain cosmology, time is without beginning and eternal. The Kālacakra, the cosmic wheel of time, rotates ceaselessly. The wheel of time is divided into two half-rotations, Utsarpiṇī or ascending time cycle and Avasarpiṇī, the descending time cycle, occurring continuously after each other. Utsarpiṇī is a period of progressive prosperity and happiness where the time spans and ages are at an increasing scale while the Avasarpiṇī is a period of increasing sorrow and immorality with decline in time spans of the epochs. During each such time cycle, these 63 illustrious persons appear and establish the religion and order in society. According to Jain cosmology, since time is eternal, infinite kalacakras have elapsed and will occur in future and hence infinite sets of these 63 illustrious persons have appeared, and will appear, to establish order and religion in their respective eras.