Shading is normally used in pencil drawings, ink drawings, charcoal drawings or any other art medium that relies on one colour to produce shades. Certain drawings will require certain types of shading; for example, a drawing which is intended to be realistic would use a form of shading that creates smooth, detailed areas of shading. Shading may also be determined by what instrument is used. For instance, an ink pen cannot produce different shades from pressure in the same way a pencil can, so a less realistic, rough style of shading may be used instead.
Also referred to as "slinky shading," hatching can be achieved by using a quick back and forth motion with the pencil. Pressure can be added to the pencil point to create darker lines, or reduced to create smooth, light lines. Normally, hatching is used diagonally and for drawings that require less detail or little shading. The lines will resemble a "Slinky" once finished and can be joined or overlapped -- however, the lines must ideally follow the same direction to constitute hatching.
Cross-hatching uses the same principle techniques as hatching. "Slinky" type lines are drawn and overlapped by another set of lines in another direction. Pressure can be added again to create darker shades, or more lines can be added over hatched areas to create deeper textures and dark shading tones. The closer the lines are, the darker the shading is on the drawing. This method is also popular for pen and marker pen drawings.
Smooth shading, also referred to as "charcoal shading," as charcoal is a more effective tool to use, is a technique that requires light, smooth strokes of the drawing instrument to create smooth sections of shading. Unlike hatching or cross-hatching, smooth shading does not leave patches or white areas within the shading, and is instead blended into the picture and other shading tones. A small amount of pressure is applied to the pencil in smooth shading to create a small layer of graphite (if a pencil is used), which is gradually built up by more smooth graphite layers. To create a smoother effect, use charcoal or use the pencil on a right angle, not the tip.
Pointillism, or "stippling," is a common form of shading used for ink drawings or pictures that do not require detailed shading. Light dots are created on the area which requires shading and, much like cross-hatching, the dots are built upon, overlapped and made darker to indicate different shading tones. The closer the dots are to each other, the darker the shading in that area. Highlights can be formed from the spaces between the dots and variations in shading can be easily created by darker or larger dots in a shaded area.