In this tutorial you will learn how to make realistic 3D looking text and shapes. Photoshop is not 3D software, however we can use old school combined with some modern techniques to fake it the best we can.
This tutorial illustrates a simple techique to create a sphere in Photoshop. You could have done this by using a radial gradient. Both ways give an illusion of a 3D sphere, but their effect is a little different.