Newton's Divided Difference is a numerical method used for polynomial interpolation. It helps estimate the value of a function at a given point using known values at other points. This method constructs a polynomial that passes through a set of data points, making it useful in various fields like engineering and computer science. The divided difference is calculated using a recursive formula, which simplifies the process of finding coefficients for the polynomial. By organizing the data in a table, one can efficiently compute the necessary differences, leading to a polynomial that approximates the function closely within the range of the given data points.