Private religious devotion or mental exercise, in which techniques of concentration and contemplation are used to reach a heightened level of spiritual awareness.
The practice has existed in all religions since ancient times. In Hinduism it has been systematized in the school of Yoga . One aspect of Yoga, dhyana (Sanskrit: "concentrated meditation"), gave rise to a school of its own among the Buddhists, becoming the basis of Zen . In many religions, meditation involves verbal or mental repetition of a single syllable, word, or text (e.g., a mantra ). Visual images (e.g., a mandala ) or mechanical devices such as prayer wheels or rosaries can be useful in focusing concentration. In the 20th century, movements such as Transcendental Meditation emerged to teach meditation techniques outside a religious context.