How would you describe irony? The best description of the word that I have ever heard is "stimulated ignorance." In other words, it's ignorance by design, and sometimes the design is in your control, and other times, it's not. The end result is a state of affairs that is in direct contradiction with what you'd expect. And that, my friends, is the central idea of situational irony.
It all sounds a bit complicated, but in truth, this kind of irony is usually pretty easy to pick up on, and totally hilarious. Take, for instance, these 40 photos. Each one of them in a glorious example of situational irony, and each one might even be more ironic than the next. If loving the irony of #33 is wrong, I don't want to be right.