A nun is a member of a religious community of women, typically one living under vows of poverty, chastity, and obedience. She may be a woman who decided to dedicate her life to serving all other living beings or to be an ascetic who voluntarily chooses to leave mainstreamsociety and live her life in prayer and contemplation in a monastery or convent. The term "nun" is applicable to Catholics (eastern and western traditions), Orthodox Christians, Anglicans, Lutherans, Jains, Buddhists, Taoists, and Hindus, among other religions.
While in common usage the terms "nun" and "Sister" are often used interchangeably (the same title of "Sister" for the individual member of both forms), they are considered different ways of life, with a "nun" being a religious woman who lives a contemplative and cloistered life of meditation and prayer for the salvation of others, while a "Religious Sister", in religious institutes like Mother Teresa's Missionaries of Charity, lives an active vocation of both prayer and service, often to the needy, sick, poor, and uneducated.
Buddhism is a religion indigenous to the Indian subcontinent that encompasses a variety of traditions, beliefs and practices largely based on teachings attributed to Siddhartha Gautama, who is commonly known as the Buddha, meaning "the awakened one". The Buddha lived and taught in the eastern part of the Indian subcontinent between the 6th and 4th centuries BCE. He is recognized by Buddhists as an awakened or enlightened teacher who shared his insights to help sentient beings end their suffering (dukkha) through the elimination of ignorance (avidyā) by way of understanding and the seeing of dependent origination (pratītyasamutpāda) and the elimination of craving (taṇhā), and thus the attainment of the cessation of all suffering, known as the sublime state of nirvāņa.
Two major branches of Buddhism are generally recognized: Theravada ("The School of the Elders") and Mahayana ("The Great Vehicle"). Theravada has a widespread following in Sri Lanka and Southeast Asia (Cambodia, Laos, Thailand, Myanmar etc.). Mahayana is found throughout East Asia (China, Korea, Japan, Vietnam, Singapore, Taiwan etc.) and includes the traditions of Pure Land, Zen, Nichiren Buddhism, Tibetan Buddhism, Shingon, and Tiantai (Tendai). In some classifications, Vajrayana—practiced mainly in Tibet and Mongolia, and adjacent parts of China and Russia—is recognized as a third branch, while others classify it as a part of Mahayana.