Data Interpolation is a mathematical technique used to estimate unknown values that fall within a range of known data points. By analyzing the existing data, interpolation helps create a smooth curve or line that predicts values at specific intervals, making it useful in various fields like science, engineering, and finance. There are several methods of interpolation, including linear interpolation, which connects two known points with a straight line, and polynomial interpolation, which uses polynomials to fit a curve through multiple points. These techniques enable better data analysis and visualization, enhancing decision-making processes.