Images are depictions in two dimensions. In other words, an image has length and width but not depth. An image is a representation of something on a flat plane: a person, animal, object, or element of landscape. Images can be simple, focusing on one element, such as a house or a person, or even alphabetic letters such as logos or calligraphy. Images can also be complex, layering and assembling individual images. Murals and landscapes
are complex images. Often surfaces are covered with multiple images that are related to each other either in sequence or by association. Images in comic strips relate to each other sequentially.
Images are related to other images by association when putting them together creates a meaning greater than the single image. Photographs that show officials meeting together suggest a commonality of purpose by association. Likewise, images of people show modes of dress and often furnishings. The person, clothing, and furnishings are associated together. The style of dress or furnishing, whether elaborate or simple, is deeply involved in the culture and communicates a meaning greater than any one element.
Images can be fashioned to give the illusion of depth. Societies have accomplished this in many different ways. Today we are most familiar with what are called single-point or retinal-perspective images in which objects in the distance appear smaller. Many societies understand the mathematics of creating such an image, so that depth is represented as the eye perceives it. Yet many societies have chosen to indicate depth in images in different ways, and often create devices (such as shadows and holographic techniques) to show depth.
Most common among ways of conceptualizing depth are layeringputting images of the same size in front of one anotherand rows. With rows, the upper part of the image appears to be further away and the lower part appears closer to the viewer. Many medieval manuscripts from the Middle East use this technique. Color layering is a technique frequently used in billboard advertising in the 20th and 21st centuries. Bright, saturated colors are used to foreground an object, usually the item to be purchased, while other figures are depicted in shades of gray that are to be perceived as the background.
Images have material existence. They have surfaces, color, pattern, and texture. From the earliest known images to those in the contemporary world, the substance of the image is related to its meaning. Images can be static. Images can be moved, carried, and displayed by various people and to various audiences. Images can also move. Moving images, or movies, are among the most recent methods for creating and representing something visually.