When studying the mathematical statistics, I notice that there is some confusion between the notations of conditional probability and giving parameters to the probability function.
I am confused quite often when seeing these two notations are used interchangeably. For example, I understand easily that $f(x|y)$ is a conditional probability, but I am not quite confident when seeing something like $f(x|\theta)$ that $\theta$ plays a role of being parameter instead of actual conditional probability.
Is there a way to clearly tell the difference between these two notations? How can I ensure the correct notation being used in the question?