Limits are essential in mathematics, specifically in calculus. They describe the behavior of a function near a certain point rather than at that point itself. This concept is the foundation of calculus and helps us understand the behavior of functions. In most cases, limits exist, but it is important to remember that we are not discussing the value at x=∞. Rather, as the input increases, the output gets closer to a specific value. A limit is the value that a function approaches as the input approaches a certain value. It is crucial in calculus and is necessary for a function to be continuous at a point. Overall, limits play a significant role in mathematics and provide a way to describe the behavior of a function.