Modern dance is a dance form developed in the early 20th century. Although the term Modern dance has also been applied to a category of 20th Century ballroom dances, Modern dance as a term usually refers to 20th century concert dance.In the early 1900s two American female dancers, Isadora Duncan and Ruth St. Denis, as well as one German female dancer, Mary Wigman, started to rebel against the rigid constraints of Classical Ballet. Shedding the authoritarian controls surrounding classical ballet technique, costume, and shoes, these early modern dance pioneers focused on creative self-expression rather than on technical virtuosity. Modern dance is a more relaxed, free style of dance in which choreographers use emotions and moods to design their own steps, in contrast to ballet's structured code of steps. It has a deliberate use of gravity, whereas ballet strives to be light and airy