An early 20th-century school of painting and sculpture in which the subject matter is portrayed by geometric forms without realistic detail, stressing abstract form at the expense of other pictorial elements largely by use of intersecting often transparent cubes and cones.
Cubism, highly influential visual arts style of the 20th century that was created principally by the painters Pablo Picasso and Georges Braque in Paris between 1907 and 1914. The Cubist style emphasized the flat, two-dimensional surface of the picture plane, rejecting the traditional techniques of perspective, foreshortening, modeling, and chiaroscuro and refuting time-honoured theories of art as the imitation of nature. Cubist painters were not bound to copying form, texture, colour, and space; instead, they presented a new reality in paintings that depicted radically fragmented objects, whose several sides were seen simultaneously.
Cubistic provides a stimulating site on all things cubist
A Treatise on Cubism can be found here
Many examples can be found following this link
These Pictures represent two stages in Pablo Picasso’s Cubist period:

Pablo Ruiz Picasso
Maisons
sur la colline (Horta de
Ebro). Horta.
Summer/1909. 65 x 81
cm. Oil on canvas.
Museum of
Modern Art, NYC

Three Women
This next example is by Igal Koshevoy

"Wratheon," Igal Koshevoy
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