In countries where Theravāda Buddhism is practiced by the majority of people, such as Sri Lanka, Cambodia, Laos, Burma, Thailand, it is customary for Buddhists to hold elaborate festivals, especially during the fair weather season, paying homage to the 28 Buddhas described in the Buddhavamsa. The Buddhavamsa is a text which describes the life of Gautama Buddha and the 27 Buddhas who preceded him. The Buddhavamsa is part of the Khuddaka Nikāya, which in turn is part of the Sutta Piṭaka. The Sutta Piṭaka is one of three main sections of the Pāli Canon of Theravāda Buddhism.
The first three of these Buddhas—Taṇhaṅkara, Medhaṅkara, and Saraṇaṅkara—lived before the time of Dīpankara Buddha. The fourth Buddha, Dīpankara, is especially important, as he was the Buddha who gave niyatha vivarana (prediction of future Buddhahood) to the Brahmin youth who would in the distant future become the bodhisattva Gautama Buddha. After Dīpankara, 23 more noble people (ariya-puggala) would attain enlightenment before Gautama, the historical Buddha.
Many Buddhists also pay homage to the future (and 29th) Buddha, Maitreya. According to Buddhist scripture, Maitreya will be a successor of Gautama who will appear on Earth, achieve complete enlightenment, and teach the pure Dharma. The prophecy of the arrival of Maitreya is found in the canonical literature of all Buddhist sects (Theravāda, Mahāyāna, and Vajrayāna), and is accepted by most Buddhists as a statement about an event that will take place when the Dharma will have been forgotten on Jambudvipa (the terrestrial realm, where ordinary human beings live).