Ways of Representing a Subject

Subjects are represented in many ways. Its manner varies according to the creativity and purpose of each artist. The artist may use realism, abstraction or distortion.

Realism

Realism as a way to represent a subject means depicting the subject normally as it appears in nature.  Even if how realistic is the work of an artist, strictly speaking, it is not truly realistic. As Ortiz, et al (1976) put it, "no work of art is truly realistic since no work of art is an accurate  copy of what exists in the natural world."

Let us not be confused with realism as a way to present a subject and realism as an art movement. (Read: Realism Movement, Artists and Major Works | The Art Story)

There are paintings which seem to be photographic renderings of facts that you might have a second thought whether you are looking at photographs or paintings. A lot of examples can be found in this site. 

Abstraction

Abstraction is a process of simplifying and/or reorganizing objects and elements according to the demands of artistic expression. The artist selects and renders the objects with their shapes, colors and positions altered (Ortiz, et al, 1976). Sometimes an artist becomes so interested in one phase of a scene or a situation that the subject is not shown as an objective reality, but only as the artist's idea of it or feeling about it. For example, Brancusi is impressed by the grace of the bird in flight, by the sweep of its body as it flies through the air, so he tries to represent those qualities in his statute Bird in Space. It does not look like a bird, and it is not supposed to look like a bird. It is supposed to convey an impression of a bird's grace and speed (Dudley, Faricy and Rice, 1978). 

It is to be remembered, however, that abstract arts can be representational or  non-representational. Brancusi's Bird in Space is an abstract work and  it has a subject. For those abstract works without subject, a more exact term is non-objective.

Some works of art are close to realism, others are close to abstraction. Therefore, between these two ways, there are still  many ways of presenting the subject. (Check El Greco's works and Henry Moore's sculptures.) 

Whose work is closer to realism? to abstraction?

Distortion

When an artist changes  the original shape of an object, the object is said to be distorted. Ancient Egyptian relief sculptures and paintings were usually distorted. There are parts of the body which were shown in profile position while the rest were frontal.

Distortion is usually done to dramatize the shape of a figure or to create an emotional effect (Ortiz, et al., 1976).  A political art  like  caricature is an example. Caricatures use distortion to make the objects of ridicule appear ugly and hateful. The works of a surrealist painter, Marc Chagall, and an expressionist, Edvard Munch, can also be used as examples of this category.