Drawing is a visual process of using lines to create forms, shapes, and details to represent ideas. In art, drawing is a fundamental discipline practiced with mediums such as pencils, pens, graphite, or a digital stylus on computers. In the field of observational and imaginative painting, a strong understanding of drawing principles is essential before beginning to learn painting. This is due to drawing's strong focus on understanding forms over understanding light. Drawing, much like reading and writing, is a skill anyone can learn. It's comprised of many theories based on concepts such as light, form, and principles behind the visual world. Lines, often considered abstract and not existing in reality, represent edges, or to some extent represent shadows.