Septic pumping companies have some cool diagrams. This graphic shows what everything looks like underground with a septic system. You get the idea of how it is distributed into the ground after bacteria break it down in the tank.
Septic Tank Tip An inexpensive way to keep your septic system working properly, is to take one packet of dry yeast and a box of brown sugar and pour this down your toilet about every months. (Our new house has a septic system )