Spline interpolation is a mathematical method used to estimate values between known data points. It involves creating a smooth curve, called a spline, that passes through or near these points. This technique is particularly useful in computer graphics and data analysis, as it provides a more accurate representation of the underlying data compared to simpler methods like linear interpolation. The most common type of spline is the cubic spline, which uses piecewise cubic polynomials to connect the data points. Each segment of the spline is defined by a cubic equation, ensuring that the curve is smooth and continuous at the data points, making it ideal for applications requiring precision.