There's a huge difference between being an investor and being a trader. That distinction is crucial for this article, because I'm introducing three stocks that should be making huge moves this week.

If you're a shareholder of Cirrus Logic (CRUS -0.96%)iRobot (IRBT -0.28%), or Infinera (INFN 1.40%) shares, prepare yourself for volatility. Unlike traders, who like to lock in short-term gains or cut their losses quickly, you need to be prepared to focus on the variables that really matter.

This week, these three companies will be reporting earnings, and because all three have a high proportion of their shares sold short, there will probably be a lot of volatility. To find out why so many are betting against these three -- and to see what you should really be focusing on -- check out the slideshow below.