The Wiggles are a children's musical group formed in Sydney, Australia, in 1991. Often called "the world's biggest preschool band," the group's music is based on theories of child development. They have produced videos, television programs and performed live shows, often creating a bevy of likeable characters meant to appeal to children, such as Wags the Dog, Henry the Octopus, Dorothy the Dinosaur, among others. The Wiggles tickets are a hot property for children and their parents wanting to experience their child's first "rock band."