A format for representing real (floating-point) numbers. Instead of writing the full number, scientific notation represents values as a number between 1 and 10 multiplied by 10 to some power. The 10 is often replaced by an uppercase or lowercase E.
Scientific notation is much simpler for very large and very small numbers, such as the second and fourth examples. Most programming languages, and many numeric applications, allow you to enter and display numbers using scientific notation.