So what do we mean by that? So once again let's take a look at the following coin. Now before I actually flip the coin, what can happen? Well, two events can actually take place within this one event. So two outcomes, we either get a tails or we get a head. And in a way we can see those two outcomes as two mutually exclusive events because once this actually takes place and I get tails, then heads cannot actually take place because tails already took place.