Aluminum foil
Aluminum foil is not a light source.
Laptop and Tablet
Laptops and tablets are light sources.
Firefly
A firefly is a light source.
Reflective Jacket
A reflective jacket is not a light source.
Lightning
Lightning is a light source.
Glass window
A glass window is not a light source.
Campfire
A campfire is a light source.
Diamond
A diamond is not a light source.
Fireworks
Fireworks are a light source.
Flashlight
A flashlight is a light source.
