He was an important contributor to the De Stijl art movement and group, which was founded by Theo van Doesburg. Despite being well-known, often-parodied and even trivialized, Mondrian's paintings exhibit a complexity that belies their apparent simplicity. He is best known for his non-representational paintings that he called compositions, consisting of rectangular forms of red, yellow, blue, white or black, separated by thick, black rectilinear lines. They are the result of a stylistic evolution that occurred over the course of nearly 30 years and continued beyond that point to the end of his life.

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De Stijl : also known as neoplasticism, was a Dutch artistic movement, founded in 1917. In a narrower sense, the term

De Stijl is used to refer to a body of work created by a group of Dutch artists, from 1917 to 1931.

Theo van Doesburg: Theo van Doesburg was a Dutch artist, practicing in painting, writing, poetry and architecture. He is most famously known as the founder and leader of De Stijl.