Lighting is where the magic happens. This is true for both photography and 3D art.
I have noticed many times that newcomers to the field of 3D art tend to focus on a series of technical issues—texture resolution, antialiasing, SSS, for example—and spend comparatively smaller amounts of energy in learning about lighting. The harsh reality is that great lighting will do more for the final quality of your image than anything else. Great lighting upstages texture resolution and even material definition.
Learning about lighting is, therefore, one of the most important tasks facing a 3D artist, no less important than it is for a photographer.
We cannot condense all there is to learn about lighting in one chapter—it takes years of practice to become proficient in this field—but we will see some of the basic principles that can guide us in the process of learning about the wonderful art of painting with light.