Exponential notation is a way to express large or small numbers using powers of ten. In this system, a number is written as a base multiplied by ten raised to an exponent. For example, the number 5,000 can be written as 5 × 10^3, where 3 indicates that 10 is multiplied by itself three times. This notation simplifies calculations and makes it easier to read very large or very small numbers. For instance, the speed of light, approximately 299,792,458 meters per second, can be expressed as 2.99792458 × 10^8. This format is widely used in science and engineering.