Euler's Number, denoted as e, is a special mathematical constant approximately equal to 2.71828. It is named after the Swiss mathematician Leonhard Euler, who made significant contributions to its study. e is important in various fields, especially in calculus, where it serves as the base for natural logarithms. This makes it essential for understanding growth processes, such as population growth and compound interest. One fascinating property of e is that it appears in many real-world applications, including finance and biology. For example, when calculating compound interest, the formula involves e to determine how money grows over time. Its unique characteristics make it a cornerstone of mathematics and science.