Gryphem Challenge: The Billiard Ball Puzzle

One of the goals of Gryphem is to get you thinking.  This particular post, rather than using real world observations to get you thinking, does so with a logic puzzle.  Welcome to the first Gryphem Challenge.

The Billiard Ball Puzzle

You are given twelve billiard balls identical in appearance.  Eleven of these are of the same weight, but one is of a different weight.  You are given a set of balancing scales.

The Challenge

Use the scales and your intelligence to identify the billiard ball that is of a different weight (the oddball), and tell whether it is heavier or lighter than the others.  Complete this process in the fewest possible number of steps (weighings).  You must be able to logically demonstrate that your process will work in every case.

Your Response

Discover and tell the minimum number of steps (weighings) required to meet the challenge.  Explain the process in order to demonstrate the accuracy of your response.

Checking Your Solution

One possible response is provided.  There may be others.  Your explanation does not have to be in the same format as the one provided.  Do make an effort yourself before you scroll down beyond the intelligent penguin below to see the solution provided.

You can do it.  You have the power.

Gryphem

And Heeere's the Solution...
(Click on the picture to make it larger.)

The objective can be accomplished in only 4 steps.  This diagram shows the first two steps.

This diagram shows the third and fourth steps.  I hope you did well...  Thanks for playing.