Conceptual art

Conceptual art is art in which the concepts or ideas involved in the work are more important than traditional aesthetic and material concerns. Many of the works, sometimes called installations, may be constructed by anyone simply by following a set of written instructions. This method was fundamental to one of the first to appear in print:
Conceptual art even questions the nature of art. Joseph Kosuth elevated this into a definition of art itself in his early manifesto of conceptual art. 
The notion that art should examine its own nature was already part of art critic Clement Greenberg's vision of modern art during the 1950s. With the emergence of an exclusively language-based art in the 1960s, however, conceptual artists began a far more radical analysis of art than was previously done. One of the first things they questioned was the assumption that the role of the artist was to create special kinds of material objects.
Conceptual art has come to mean all contemporary art which does not use the traditional skills of painting and sculpture.