The min-raise is used by players in a variety of situations. One of the most common applications is when the flop reveals a potential draw. Consider a flop that brings two diamonds, thus a potential flush draw. You flop top pair, so you bet 80% of the pot or so. The player to your left immediately raises you the minimum by clicking the "raise" button. This action immediately suggests that he's on a draw. It's unlikely that he would immediately raise a set since he has position on you....

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