We won't say it's imperative...but it is somewhat significant to understand how common investments operate. If you're going to move some money into an investment, probably a good idea to be able to answer "why" you did so. ETF's are a popular investment for people looking to put their hard earned dollar to work. We've covered how mutual funds are more "active" in nature. Prop your feet up for this one, and relax. We expose the laid back, "passive" qualities of ETF's.