What is the difference between expressionism and impressionism?

Before the appearance of impressionism, for a long time the only recognized artistic method was realism. Throughout centuries, artists painted relatively the same motifs, and although many painters possessed their own style, in general it can be said that there was little variety in the ways of depicting reality; the main goal was to depict things as seen by the artist. This changed, however, in the 19th century, with the emergence of impressionism – the direction in art whose main purpose was to give a viewer an impression of reality, and not to depict it as precisely as possible. Impressionism is not opposite to realism – it is rather the further development and enhancement of the principles underlying classic art. It is what viewers felt when looking at the picture which was important. Through the exaggeration of colors, different stroke techniques (pointillism, for instance), non-standard scenes, and other ways, artists managed to change the usual way people perceived paintings, appealing to their emotions rather than sight. In its turn, expressionism has its focus more on the artist’s emotions rather than on those of a viewer. An artist can play with the depicted reality however they feel like, with the main goal being to express the inner world – thoughts, emotions, mood–of a painter. Sometimes it can be difficult to distinguish expressionism from impressionism (for example, Edvard Munch’s paintings – other than his famous “The Scream” – can be related to both directions), but expressionism usually goes deeper in its manipulations with reality; abstract art, for instance, can be related to expressionism. In general, it can be said that impressionism is what the viewer feels, and expressionism is what is felt by the artist.