Scientific illustration is as the name suggests: illustration with a scientific purpose. It is as diverse as science itself. The most commonly known example of scientific illustration may be medical or botanical illustration. But you can also think of zoological, archeological, geological or pale-ontological purposes. Scientific illustration can be applied in many ways: in publications in a scientific journal, a presentation about a new medical procedure, a biology schoolbook, an educational poster, etc.
The task of a scientific illustrator is to take what the scientist wants to communicate to his or her audience and present it in a visually effective and aesthetically pleasing way. In order to do so the illustrator must have knowledge of the subject. A good basic understanding of anatomy is often mandatory, just as having a good eye and technical drawing skills are. Every illustration begins with a proper registration (detailed sketch) of the subject before the final illustration can be made. The rendering of the final illustration can be made traditionally, with water colour or pencil, or digitally with Photoshop or Illustrator.