Drawing. Drawing is a form of visual art in which a person uses various drawing instruments to mark paper or another two-dimensional medium. Instruments include graphite pencils, pen and ink, various kinds of paints, inked brushes, colored pencils, crayons, charcoal, chalk, pastels, various kinds of erasers, markers, styluses, and various metals. Digital drawing is the act of using a computer to draw. Common methods of digital drawing include a stylus or finger on a touchscreen device, stylus-or finger-to-touchpad, or in some cases, a mouse. There are many digital art programs and devices. A drawing instrument releases a small amount of material onto a surface, leaving a visible mark. The most common support for drawing is paper, although other materials, such as cardboard, wood, plastic, leather, canvas, and board, may be used. Temporary drawings may be made on a blackboard or whiteboard or indeed almost anything. The medium has been a popular and fundamental means of public expression throughout human history. It is one of the simplest and most efficient means of communicating visual ideas. The wide availability of drawing instruments makes drawing one of the most common artistic activities. In addition to its more artistic forms, drawing is frequently used in commercial illustration, animation, architecture, engineering and technical drawing. A quick, freehand drawing, usually not intended as a finished work, is sometimes called a sketch. An artist who practices or works in technical drawing may be called a drafter, draftsman or a draughtsman. Drawing is one of the oldest forms of human expression within the visual arts. It is generally concerned with the marking of lines and areas of tone onto paper/other material, where the accurate representation of the visual world is expressed upon a plane surface. Traditional drawings were monochrome, or at least had little colour, while modern colored-pencil drawings may approach or cross a boundary between drawing and painting. In Western terminology, drawing is distinct from painting, even though similar media often are employed in both tasks. Dry media, normally associated with drawing, such as chalk, may be used in pastel paintings. Drawing may be done with a liquid medium, applied with brushes or pens. Similar supports likewise can serve both: painting generally involves the application of liquid paint onto prepared canvas or panels, but sometimes an underdrawing is drawn first on that same support. Drawing is often exploratory, with considerable emphasis on observation, problem-solving and composition. Drawing is also regularly used in preparation for a painting, further obfuscating their distinction. Drawings created for these purposes are called studies. There are several categories of drawing, including figure drawing, cartooning, doodling, and freehand. There are also many drawing methods, such as line drawing, stippling, shading, the surrealist method of entopic graphomania, and tracing. A quick, unrefined drawing may be called a sketch. In fields outside art, technical drawings or plans of buildings, machinery, circuitry and other things are often called drawings even when they have been transferred to another medium by printing. Drawing is one of the oldest forms of human expression, with evidence for its existence preceding that of written communication. It is believed that drawing was used as a specialised form of communication before the invention of the written language, demonstrated by the production of cave and rock paintings around 30,000 years ago.These drawings, known as pictograms, depicted objects and abstract concepts. The sketches and paintings produced by Neolithic times were eventually stylised and simplified in to symbol systems and eventually into early writing systems. Before the widespread availability of paper, 12th-century monks in European monasteries used intricate drawings to prepare illustrated, illuminated manuscripts on vellum and parchment. Drawing has also been used extensively in the field of science, as a method of discovery, understanding and explanation. Drawing diagrams of observations is an important part of scientific study. In 1609, astronomer Galileo Galilei explained the changing phases of Venus and also the sunspots through his observational telescopic drawings. In 1924, geophysicist Alfred Wegener used illustrations to visually demonstrate the origin of the continents. Drawing is used to express one's creativity, and therefore has been prominent in the world of art. Throughout much of history, drawing was regarded as the foundation for artistic practice.