Simple interest is a method of calculating interest on a loan or investment. It is called "simple" because it is a fixed percentage of the principal amount, without any compounding of interest over time.
The formula for simple interest is: I = P * R * T, where I is the interest, P is the principal amount, R is the interest rate, and T is the time period.
Simple interest is often used for short-term loans, such as personal loans or short-term investments, where the interest is calculated on a daily or monthly basis.