An array formula in Excel is a formula that can perform multiple calculations on one or more sets of values and return multiple results. It is called an array formula because it operates on arrays of data rather than individual cells. Array formulas are enclosed in curly braces {} and must be entered into the cell by pressing CTRL + SHIFT + ENTER instead of just pressing Enter. Array formulas are useful for performing complex calculations, such as finding the maximum or minimum value in a range, summing multiple columns based on certain conditions, or performing calculations across multiple rows and columns simultaneously.
