Assumptions are beliefs or ideas that we accept as true without proof. They help us make sense of the world and guide our decisions. For example, when we assume that the sun will rise tomorrow, we base our daily plans on this expectation, even though we cannot guarantee it. In various fields, such as science and mathematics, assumptions are crucial for forming theories and models. They simplify complex situations, allowing us to focus on key factors. However, incorrect assumptions can lead to misunderstandings or errors, highlighting the importance of questioning and testing our beliefs.