Impressionism can be considered to be the first distinctly modern movement in painting. Developing in Paris in the 1860s, its influence spread throughout Europe and the United States. Its originators were artists shunned by powerful academic art institutions. They also rejected the Salon, the official, government-sanctioned exhibition which was one of the pinnacles of the French social calendar. In turning away from the fine finish and detail to which most artists of their day aspired, the Impressionists aimed to capture the immediate effect of a scene - the impression it made on the eye in a fleeting instant.

• The movement gained its name after a hostile French critic, reviewing the artists' first major exhibition, seized on the title of Claude Monet's painting: Impression, Sunrise (1873), and accused them of painting nothing but impressions. The group soon embraced the title, though they would also refer to themselves as the Independents.
• Impressionism was a style of representational art that did not necessarily rely on realistic depictions. Contemporary science was beginning to recognize that what the eye perceived and what the brain understood were two different things: the Impressionists sought to capture the former - the impact of a scene.
• The Impressionists loosened their brushwork, and lightened their palettes with pure, intense colors. They abandoned traditional perspective, and they avoided the clarity of form which, in earlier art, serves to distinguish the more from the less important elements of a picture. This resulted in many critics accusing Impressionist paintings of looking unfinished or amateurish.
• Although Impressionism is not thought to have had a powerful impact on Abstract Expressionism, one can trace important similarities between its artists' work. Philip Guston was once described as a latter-day 'American Impressionist', and the surface qualities, the suggestions of light, and the 'all-over' treatment of form in Jackson Pollock's work, all bear comparison with Monet.

Although Claude Monet is now considered one of the quintessential Impressionists, Edouard Manet was one of the style's most important innovators. He had matured in admiration of the Old Masters, but in the early 1860s he began to develop an innovative, looser handling of paint, accompanied by a brighter palette. His work is also characterized by a relaxed approach to modeling: there appear to be seamless transitions between figures and the space around them, an effect which can leave the picture as a whole seeming flat. As he matured, Manet's subject matter transitioned from more traditional subjects - religious, mythological and historical subjects - to scenes of everyday life, such as cafes, boudoirs and street scenes. And as he did so, he began to attract the fury of critics: his Absinthe Drinker (1858-9) was rejected from by the Salon, and, in 1863, his Dejeuner sur l'herbe (1862-3) created such a scandal at the Salon des Refuses that the exhibition had to be closed.

Although Manet's styled himself a gentleman rather than a bohemian, his example soon attracted the attention of artists on fringes. By the late 1860s, a small number of young painters working in Paris were beginning to discover one another through a series of small exhibits. Though not yet joined by any singular style, they were already united by a general sense of rebellion against academic standards of fine art, established at the time by the influential Paris Salon. While the highest form of art was still considered painting with historical, mythological and/or religious subject matter, artists like Claude Monet, Pierre-Auguste Renoir and Edgar Degas were painting still lifes, landscapes and portraits. Some Impressionists were also painting outdoors, and were trying to capture the effects of natural light.

In 1874, Monet unveiled his painting Impression, Sunrise (1872) at the very first independent show of the Impressionist painters. Critic Louis Leroy wrote a scathing review of the small and poorly received exhibit and mockingly referred to it as "The Exhibition of the Impressionists," taking Monet's painting title as his inspiration. Leroy paid particularly close attention to the work of Monet and Cézanne, whose paintings he maintained looked wet and unfinished.

Edouard Manet's style bridged the gap between Realism and Impressionism, and, in that sense, he was never a true Impressionist painter. Rather, he was a Realist who inspired a generation of Impressionists by embracing subject matter from everyday life, void of any religious or historical connotations. His bold and unorthodox approaches to traditional subjects - placing a nude woman in a garden scene, interacting with fully clothed men - also inspired many younger artists working in Paris.

Claude Monet is undoubtedly the most celebrated of the Impressionists. He was renowned for his mastery of natural light, and painted at many different times of day in an attempt to capture changing conditions. He tended to paint simple impressions or subtle hints of his subjects, using very soft brush strokes and unmixed colors to create a natural vibrating effect, as if nature itself were alive on the canvas. Neither did he wait for paint to dry before applying successive layers, and this 'wet on wet' technique produced softer edges and blurred boundaries which merely suggested a three-dimensional plane, rather than depicting it realistically.

Other Impressionists, like Edgar Degas, were less interested in painting outdoors, and rejected the idea that painting should be a spontaneous act. Considered a highly skilled draftsman and portrait artist, Degas preferred indoor scenes of modern life: people sitting in cafes, musicians in an orchestra pit, ballet dancers performing mundane tasks at rehearsal. He also tended to delineate his forms with greater clarity than Monet or Pissarro, using harder lines and thicker brush strokes.

Although the Impressionists proved to be a diverse group, they came together regularly to discuss their work and exhibit. The Cafe Guerbois, in Montmatre, was a regular meeting place. The group collaborated on eight exhibitions between 1874 and 1886 while slowly beginning to unravel. Many felt they had mastered the early, experimental styles which won them attention, and they wanted to explore other avenues. And some, anxious about the continued commercial failure of their work, changed course.

Meanwhile, the lessons of the style were taken up by a new generation. If Manet bridged the gap between Realism and Impressionism, then Paul Cézanne was the artist who bridged the gap between Impressionism and Post-Impressionism. Cézanne learned much from Impressionist technique, but he evolved a more deliberate style of paint-handling, and, towards the end of his life, a closer attention to the structure of the forms that his broad, repetitive brushstrokes depicted. As he once put it, he wished to "redo [Nicolas] Poussin after nature and make Impressionism something solid and durable like the Old Masters." He wished to break down objects into their basic geometric constituents, and to depict their essential building blocks. This experiment would ultimately prove highly influential on the development of Cubism by Picasso and Braque.

"There are no lines in nature, only areas of color, one against another."
-Edouard Manet

"You would hardly believe how difficult it is to place a figure alone on a canvas, and to concentrate all the interest on this single and universal figure and still keep it living and real."
-Edouard Manet

"If the painter works directly from nature, he ultimately looks for nothing but momentary effects; he does not try to compose, and soon he gets monotonous."
-Pierre-Auguste Renoir

"I am following Nature without being able to grasp her; I perhaps owe having become a painter to flowers."
- Claude Monet

"After 1918, as we know, enlightened public - as well as critical - esteem went decidedly to Cézanne, Renoir and Degas, and to Van Gogh, Gauguin and Seurat. The 'unorthodox' Impressionists - Monet, Pissarro, Sisley - fell under a shadow. It was then that the 'amorphousness' of Impressionism became an accepted idea; and it was forgotten that Cézanne himself had belonged to, and with, Impressionism as he had to nothing else."
-Clement Greenberg, from essay "The Later Monet"