Note. Unity 5 introduced the Standard Shader which replaces this shaderA program that runs on the GPU. More info
See in Glossary.
Diffuse computes a simple (Lambertian) lighting model. The lighting on the surface decreases as the angle between it and the light decreases. The lighting depends only on this angle, and does not change as the cameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
See in Glossary moves or rotates around.
Generally, this shader is cheap to render. For more details, please view the Shader Peformance page.