Gouraud shading is a computer graphics technique used to simulate the way light interacts with surfaces. It calculates the color at the vertices of a polygon and then interpolates these colors across the surface. This creates a smooth transition of colors, giving the appearance of curved surfaces and soft lighting. This method is efficient for rendering 3D objects, as it reduces the number of calculations needed compared to more complex techniques like Phong shading. However, Gouraud shading can sometimes miss finer details, such as specular highlights, making it less suitable for scenes requiring high realism.