I apologize for any confusion. An interval in math refers to a set of real numbers between two given values. It can be represented using bracket notation or interval notation. For example, the interval [a, b] includes all real numbers between a and b, including a and b themselves. On the other hand, the interval (a, b) includes all real numbers between a and b, excluding a and b themselves. Interval notation can also include infinity (∞) or negative infinity (-∞) to represent intervals that extend indefinitely in one direction.