Marcel Duchamp was one of the most influential artists of the 20th century.

image source: https://zettelmagazine.wordpress.com/2014/07/23/three-masters-of-art-and-chess/
Few artists can boast of having changed the course of art history in the way that Marcel Duchamp did. By challenging the very notion of what is art, his first readymades, such as Bicycle Wheel (1913) and Fountain (1917), sent shock waves across the art world that can still be felt today. In his insistence that art should be driven by ideas above all, Duchamp is generally considered to be the father of Conceptual art.
About his life

Born on July 28, 1887, in Blainville-Crevon, France, he studied at the Académie Julian in Paris from 1904 to 1905.
By 1911, he began hosting informal salons with his brothers Raymond Duchamp-Villon and Jacques Villon, inviting artists such as Francis Picabia, Robert Delaunay, and Roger de la Fresnaye, the group became known as the Section d’Or.
His refusal to follow a conventional artistic path, matched only by a horror of repetition which accounts for the relatively small number of works Duchamp produced in the span of his short career, ultimately led to his withdrawal from the art world.
In later years, Duchamp famously spent his time playing chess, even as he labored away in secret at his last enigmatic masterpiece, which was only unveiled after his death on October 2, 1968 in Neuilly-sur-Seine, France.
image source: https://en.wikipedia.org/wiki/Jacques_Villon
Identity and key concepts

A performative act as much as a stylistic category coined by Duchamp himself, the term “readymade” came to designate mass-produced everyday objects taken out of their usual context and promoted to the status of artworks by the mere choice of the artist.
Nude Descending A Staircase (1912)
More than a study of the body’s movement through space, the oil painting is an early figurative exercise in painting cinematically, akin to Eadweard Muybridge’s sequences of photographs that anticipated motion pictures.

image source: https://en.wikipedia.org/wiki/File:Duchamp_-_Nude_Descending_a_Staircase.jpg
Fountain (1917)
Fountain is a readymade sculpture: a porcelain urinal signed “R.Mutt” which orientation was altered from its usual positioning. Showing art primarily as a concept rather than an object, is what would make Fountain arguably the most intellectually captivating and challenging art piece of the 20th century.

image source: https://elamarthistory.com/slide-lists/modernism-before-the-wars/duchamp-fountain-1917/
info source: https://en.wikipedia.org/wiki/Marcel_Duchamp