Meditation involves calming the mind and relaxing the body to reduce stress and anxiety. There are two main types: mindfulness meditation which focuses on present thoughts and feelings, and concentrative meditation which focuses on a particular object. Meditation can help with conditions like anxiety, depression, hypertension, and insomnia by lowering heart rate, blood pressure, and oxygen consumption. Some individuals may experience negative reactions like hypersensitivity or exacerbation of psychosis.