More and more museum directors are realizing that people learn best when they can somehow become part of what they are seeing. In many science museums, for example, there are no guided tours. The visitor is encouraged to touch, listen, operate, and experiment so as to discover scientific principles for himself. He can have the experience of operating a spaceship or a computer. He can experiment with glass blowing and papermaking. The purpose is not only to provide fun but also to help people feel at home in the world of science. The theory is that people who do not understand science will probably fear it, and those who fear science will not use it to the best advantage. Many museums now provide educational services and children's departments. In addition to the usual displays, they also offer film showings and dance programs. Instead of being places that one "should" visit, they are places to enjoy.