In this talk I will briefly introduce the definitions of limiting pairs, potential pairs, polarized pairs and their basic properties. The notion of potential pairs is inspired by the notion of "potentially klt pairs" defined in Choi-Park. I will also discuss the relation between potential pairs and (generalized) polarized pairs which firstly appeared in Birkar-Hu and Birkar-Zhang, and the minimal model theory on these pairs. With the method from MMP it can be shown that a potential pair with some extra assumption will be a generalized polarized pair. Some other related questions will be discussed too.