The word "photograph" means 'light drawing.' Light defines objects and allows us to see them. Artists create the illusion of light by producing a wide range of tonal and color values. Value is one of the seven elements of art, alongside line, shape, form, texture, color, and space. Value is how light or dark a given color or hue is.

Values are best understood when visualized as a scale or gradient, ranging from pure white to absolute black with various gray tones in between. Any hue has a similar scale from dark to light. Different values are created by lightening a hue with white or darkening it with black.

An artwork with many tones between black and white is considered low contrast, as demonstrated by a photograph with many shades of gray. Conversely, a high-contrast image has very few tonal values between black and white, as shown in another photographic example.

The texture of an object's surface influences how we perceive value. For instance, veins in lettuce leaves can create dramatic contrast, while the dull surface of banana skins results in less contrast due to their light-dulling properties.

The way artists create lines and implied textures affects value perception. A charcoal drawing might feature heavy and dark blacks with smooth transitions from dark to light, whereas a watercolor painting may have less dark blacks and less smoothly blended shading.

When observing art, pay attention to how artists render value. When creating your own artwork, practice making value scales with different mediums and hues to enhance the unique quality of your work.