Meditation is a practice where an individual operates or trains the mind or induces a mode of consciousness to allow the mind to engage in peaceful thoughts. Meditation is often used to clear the mind, reduce stress, promote relaxation or train the mind. It may be done while sitting, repeating a mantra, and closing the eyes in a quiet environment.

Meditation has been practiced since antiquity in numerous religious traditions and beliefs. Since the 19th century, it has spread from its Asian origins to Western cultures where it is commonly practiced in private and business life. Meditation is under psychological, neurological, and cardiovascular research to define its possible health effects.

The history of meditation is intimately bound up with the religious context within which it was practiced. Some authors have even suggested the hypothesis that the emergence of the capacity for focused attention, an element of many methods of meditation may have contributed to the latest phases of human biological evolution. Some of the earliest references to meditation are found in the Hindu Vedas of India. Wilson translates the most famous Vedic mantra "Gayatri" as: "We meditate on that desirable light of the divine Savitri, who influences our pious rites" (Rigveda : Mandala-3, Sukta-62, Richa-10). Around the 6th to 5th centuries BCE, other forms of meditation developed via Confucianism and Taoism in China as well as Hinduism, Jainism, and early Buddhism in Nepal and India.

In the west, by 20 BCE Philo of Alexandria had written on some form of "spiritual exercises" involving attention (prosoche) and concentration and by the 3rd century Plotinus had developed meditative techniques.

The Pāli Canon, which dates to 1st century BCE considers Indian Buddhist meditation as a step towards liberation. By the time Buddhism was spreading in China, the Vimalakirti Sutra which dates to 100 CE included a number of passages on meditation, clearly pointing to Zen (known as Chan in China, Thiền in Vietnam, and Seon in Korea). The Silk Road transmission of Buddhism introduced meditation to other Asian countries, and in 653 the first meditation hall was opened in Singapore. Returning from China around 1227, Dōgen wrote the instructions for zazen.

 The Islamic practice of Dhikr had involved the repetition of the 99 Names of God since the 8th or 9th century. By the 12th century, the practice of Sufism included specific meditative techniques, and its followers practiced breathing controls and the repetition of holy words.[29] Interactions with Indians, Nepalese or the Sufis may have influenced the Eastern Christian meditation approach to hesychasm, but this cannot be proved.  Between the 10th and 14th centuries, hesychasm was developed, particularly on Mount Athos in Greece, and involves the repetition of the Jesus prayer.

Western Christian meditation contrasts with most other approaches in that it does not involve the repetition of any phrase or action and requires no specific posture. Western Christian meditation progressed from the 6th century practice of Bible reading among Benedictine monks called Lectio Divina, i.e. divine reading. Its four formal steps as a "ladder" were defined by the monk Guigo II in the 12th century with the Latin terms lectio, meditatio, oratio, and contemplatio (i.e. read, ponder, pray, contemplate). Western Christian meditation was further developed by saints such as Ignatius of Loyola and Teresa of Avila in the 16th century.

Secular forms of meditation were introduced in India in the 1950s as a Westernized form of Hindu meditative techniques and arrived in Australia in the late 1950s and, the United States and Europe in the 1960s. Rather than focusing on spiritual growth, secular meditation emphasizes stress reduction, relaxation and self-improvement.  Both spiritual and secular forms of meditation have been subjects of scientific analyses. Research on meditation began in 1931, with scientific research increasing dramatically during the 1970s and 1980s. Since the beginning of the '70s more than a thousand studies of meditation in English-language have been reported. However, after 60 years of scientific study, the exact mechanism at work in meditation remains unclear.