Taoism (also spelled Daoism) refers to a philosophy and a religious tradition that emphasizes living in harmony with the Tao , the source and essence of everything that exists. The Chinese word Tao (or Dao, depending on the romanization system used) is usually translated as "way", "path" or "principle", although this usage takes its meaning from "reality" or "nature", which the word Tao can also mean. The proper path in life, says Taoism, is one that works in harmony with reality, the essence of the natural universe.

         The keystone work of literature in Taoist philosophy is the Tao Te Ching, a concise book containing teachings attributed to Laozi, or "the Old Teacher", in ancient China. A number of widespread beliefs and practices that pre-dated the writing of the Tao Te Ching were also incorporated into religious Taoism. After Laozi the literature of Taoism grew to vast proportions as the inherited beliefs and practices continued to evolve. The philosophy, its literature, and the religious rituals profoundly influenced the culture of China and surrounding societies in Asia. Philosophical Taoism, individualistic by nature, is not institutionalized. Religious Taoism has been institutionalized for centuries and has been influenced by a variety of cultures and traditions. Today the philosophy exercises a profound influence on modern thought worldwide: the Tao Te Ching is, after the Bible, the book most often translated into English. Religious Taoism, though it travels less readily from its Asian roots, claims adherents in a number of societies.

            Taoist propriety and ethics emphasize the Three Jewels of the Tao: compassion, moderation, and humility, while Taoist thought generally focuses on nature, the relationship between humanity and the cosmos ; health and longevity; and wu wei (action through inaction). Harmony with the universe and its source (Tao) is the intended result of Taoist practices.
Religious Taoism traditionally features reverence for ancestors and immortals along with a variety of divination practices. Clerics of institutionalised religious Taoism (Dàoshi) often take care to note distinctions between their ritual tradition and the customs and practices found in popular ("folk") religion. Chinese alchemy (including Neidan), astrology, cuisine, Zen Buddhism, several Chinese martial arts, traditional Chinese medicine, feng shui, and many styles of qigong have been intertwined with Taoism throughout history.