Transcendental meditation is a particular form of silent mantra meditation. Maharishi Mahesh Yogi created and introduced the TM technique and the TM movement in India in the mid 1950’s. The Maharishi taught thousands of people during a series of world tours from 1958 to 1965, expressing his teachings in spiritual and religious terms. TM became more popular in the 1960s and 1970s, as the Maharishi shifted to a more technical presentation, and his meditation technique was practiced by celebrities. At this time, he began training TM teachers and created specialised organisations to present TM to specific segments of the population such as businesspeople and students. By the early 2000s, TM had been taught to millions of people; the worldwide TM organisation had grown to include educational programs, health products, and related services. The TM technique involves the use of a silently-used sound called a mantra, and is practiced for 15–20 minutes twice per day. It is taught by certified teachers through a standard course of instruction, which costs a fee that varies by country. According to the Transcendental Meditation movement, it is a non-religious method for relaxation, stress reduction, and self-development. This practice is good for those who like structure and is supportive to those who are serious about maintaining a meditation practice.