"What if" is a phrase used to introduce a hypothetical scenario or question that asks someone to imagine what might happen or what might have happened. It is a suppositional question that is often used to explore alternative possibilities or to consider the consequences of different choices or actions. "What if" scenarios can be useful for brainstorming, problem-solving, and decision-making, but they can also lead to overthinking and anxiety if taken too far. In contrast, "what is" refers to the present reality or the current state of things. It is a way of focusing on what exists or what is known, rather than speculating about what might happen. Both "what if" and "what is" can be useful in different contexts, depending on the situation and the goals of the person using them.