Lagrange interpolation is a mathematical method used to estimate the value of a function at a specific point based on known values at other points. It constructs a polynomial that passes through a given set of data points, allowing for the prediction of values between these points. This technique is particularly useful in numerical analysis and computer graphics. The formula for Lagrange interpolation involves creating basis polynomials for each data point, which are then combined to form the final polynomial. This method is advantageous because it does not require solving a system of equations, making it straightforward to implement for small datasets.