Let's start this article by stating that the 13 ways of looking at risk described are in no way intended to be a comprehensive catalogue. I do hope to convey some of the nuances around risk, as well as to offer a framework for how investors can think about the various forms of risk in light of their own portfolios and plans.
At the same time, I don't mean to overcomplicate your investing life by suggesting that you need to take all of these measures into account. I would suggest instead that it's important to be aware of the range of possible risks and to pick and choose those that are appropriate to the specific goals, personal situation, and investment puzzle that you may be seeking to solve at any given moment in your investing lifetime.