Gustave Caillebotte (1848–1894) was part of the French Impressionist art movement, the first school of art to break away from classical painting. Impressionism focuses on the light and colors of a particular moment in time. Because artists wanted to capture a brief moment and didn't have cameras yet, they needed to paint quickly. So they used quick, flat strokes without precise detail.
They also used colors in new ways. The best example is that shadows aren't just the object's color with gray or brown mixed in. Instead, the painters added strokes of the complementary color of the object (e.g., strokes of red in the shadow of something green). This makes the shadows come alive.
Caillebotte is best known for his use of extreme perspective. He shows city streets from above, as though looking down from a roof. Street scenes seem to disappear into the far distance. Some viewers at the time found the unusual perspective disturbing.
Since Caillebotte was born into a wealthy Parisian family, he never needed to sell his paintings and didn't produce as many as other artists. But he contributed a great deal to the Impressionist movement as a patron. He used his wealth to support other artists. He bought paintings, financed exhibits, and even paid the rent for Claude Monet's studio. At the time of his death, he had collected 68 paintings by his favorite Impressionist artists.