Sketching traditionally refers to a preliminary rough type of drawing that an artist might make in preparation for either a painting or a more formal drawing (like a study). A sketch is less detailed than a study - a study may be a highly detailed rendition of something to be used in a large composition. Sketching is the practice of drawing a rough outline or rough draft version of a final piece of art. Sketching can be used in preparation for a large piece of art, or to just get an idea of how something will look.