In the below video, Wolfcrow’s Sareesh Sudhakaran explains the four types of light: hard light, soft light, specular and diffused light.
As he says, “The difference between hard light and soft light is pretty simple. The answer doesn’t lie in the light but in the shadows. When the shadows are sharp and clear-cut, the light is said to be a hard light. When the shadows are blurry, the light is said to be a soft light.”