Modern yoga gurus are people widely acknowledged to be gurus of modern yoga in any of its forms, whether religious or not. The role implies being well-known and having a large following; in contrast to the old guru-shishya tradition, the modern guru-follower relationship is not secretive, not exclusive, and does not necessarily involve a tradition. Many such gurus, but not all, teach a form of yoga as exercise; others teach forms which are more devotional or meditational; many teach a combination. Some have been affected by scandals of various kinds.