The Extrude PropertyManager defines the characteristics of extruded features. You can create these types of extruded features:

Solid or thin Cut
Boss/base Surface
You can also use Instant3D and Rapid Sketch to create extrudes.
When you create an extrude of a slot sketch, you can view the slot's central temporary axis. This capability is particularly useful for mating fasteners at the center of slots in assemblies.