The modern art/contemporary art movement of Dadaism was in its prime from the period of 1916 to 1920. In 1916 Hugo ball (a German poet) was exiled and set up a cafe in Zurich called the Cabaret Voltaire. Bohemian artists, musicians and writers frequented the cafe creating an atmosphere that emphasized artistic freedom and creation.
The modern art/contemporary art movement of Dadaism was about anti art in the sense of rebelling against the former traditional ideals of art. The Dada artists, musicians, poets and performers, many of them world war 1 veterans had become cynical of humanity after witnessing the extent of what man can inflict upon one another and had become disillusioned by art.
The ideal of the modern art/contemporary art movement of Dadaism was to fight art with art. A great example is Marcel Duchamp's 'L.H.O.O.Q' which mocks the mona Lisa by installing a mustache on her face. The idea of Dada was to offend and shock the art world.
It is amusing that although the idea of Dadaism was to offend, the movement became hugely influential in the art world and shifted new ways of thinking.
Why the word Dada for this modern art/contemporary art movement? What does it mean? Some believe that the word Dada originates from romainian, Da meaning 'yes' or 'yeah'. Tristan Tzara and Marcel Janco were heavily involved in creating the movement. A more artistic view of the origin of the name is that the name was founded by artists randomly stabbing a French German dictionary and landed upon the word Dada which is French for 'hobby-horse'.
The Dadaist musicians believed that they invented a new style of music. They adopted ethnic chants which appeared to have no form, structure or order and accompanied the chants with a large drum. The performers wore black faces. The Dada musicians and performers believed that the chants were a means of providing chaos and disorder.
The modern art/contemporary art movement of Dadaism wasn't coherent. The artists couldn't create art to respond to the theater and music being provided by Dada musicians and performers.
The modern art/contemporary art movement of Dadaism was a strong influence for Surrealism which followed later.