How does Gouraud shading create smoother-looking computer graphics?

In computer graphics, Gouraud shading creates smoother-looking images by improving upon the limitations of flat shading, which applies a single color tone to an entire object face and results in an unrealistic appearance.1

In Gouraud shading, the process works as follows:

• Color Calculation: The computer calculates the color for each vertex (corner) of a polygon, taking into account the specific lighting conditions at those points.1
• Interpolation: Instead of using a single color for the entire face, the computer performs interpolation—calculating intermediate color values—across the surface of the polygon.1
• Gradient Creation: This interpolation creates a smooth color gradient over each face, which effectively hides the sharp transitions between polygons and results in a much more realistic and visually smooth image.1

While more advanced techniques like Phong shading exist—which calculate lighting for every individual pixel—Gouraud shading remains a common and efficient method that modern systems can render in real time.1