Long before the days of color photography, the only way to show a product in color on a printed page was to use an illustration. Not only was the creator of the original illustration an artist, so were the craftsmen who manually reproduced the artwork on engraving plates. The process was time consuming and very expensive.

As photography progressed to color, and photosensitized engraving plates made it less expensive to print photographic images, advertisers were able to show their products in more vivid color images. Photography became the medium of choice, and many illustrators lost out, leaving room for only the very best. Those who survived, became more sophisticated, creating much of their artwork for institutional, editorial and special promotional purposes. Airbrush artists created surreal scenes impossible to reproduce with any camera. Perhaps the most recognizable being the Joe Camel promotions.

Like the color camera before, the computer has overshadowed the airbrush artist. Digital cameras and computer generated graphics programs provide the computer artist not only the ability to create the surreal, but now it allows the artist to combine the real and the unreal with an added 3rd dimension.

Computers can emulate a variety of art mediums, including airbrush. Changes are more precise and alternate variations can be easily and quickly generated at less cost.

The digital format allows easy reproduction and archiving of the image. And instead of shipping an original piece of artwork via FedEx to and ad agency, at the risk of loosing it, the artist can transmit a digital copy of his original artwork at the speed of light to any location in the world.

Unfortunately, illustrations are not used as often as they should be, especially in instruction manuals. There are some things that can not be defined very clearly with a photograph. An artist can better draw or illustrate with more detail such items as the human anatomy or complicated machinery. In fact, in most easily understood manuals you will find more illustrations than photographs.

Illustrations are especially helpful in presenting a concept. In reality, there is no other way. Since the object is non-existent, the only way to picture it is to create an illustration. Engineers and architects are concept people, however they can only illustrate their concepts in flat engineering drawings. It's the illustrator who brings visual life to the concept.

Lastly, illustrations can be used to set a mood, provoke sympathy or hatred, or make one think or act. They are often used to complement an article or an editorial in periodicals, newspapers, books, and persuade with posters. These illustrations often verge on fine art. The most famous of these are the Saturday Evening Post Cover Illustrations by Norman Rockwell.