While there are many reasons to cite your sources, here are two of the most important:
If you do not acknowledge the original ideas of others that you build upon in your own work, you engage in plagiarism, which is a major violation of the honor code.
Think about it--you wouldn't want someone claiming credit for your ideas, would you?
The same holds true when you use material that originated with others.
Let's go to Step 4 for tips on how to steer clear of this plagiarism pitfall.