The formula "πr²" is used to calculate the area of a circle. In this formula, "r" represents the radius, which is the distance from the center of the circle to its edge. The symbol "π" (pi) is a mathematical constant approximately equal to 3.14, and it represents the ratio of a circle's circumference to its diameter. To find the area, you square the radius (multiply it by itself) and then multiply that result by π. This gives you the total space contained within the circle. Understanding this formula is essential in geometry and is widely used in various fields, including architecture and engineering.