Light in photography

Quantity:
When a lot of light comes in the camera, it affects that object youre shooting. It does show as many details and it may be where you can hardly even see anything. The faster your shutter speed is, the less light gets in. More light creates a better depth of field.

Quality:
When the light is soft, or difused, that's when light's spread out on an object and you can see more of it with soft shadows and the object is brighter. By getting this affect, it comes from indirect light. Hard, or direct light, comes from spot lights, stadiums and lights that are real bright. It's concentrated and the light comes directly from the source to the object. This gives the object hard shadows and may be hard to see.

Direction:
Front light is for great details but bad for no background detail and doesn't show 3 dimensions very well. The side light is good for adding depth to something but it can make things mysterious, which can sometimes be good, and it doesn't show emotion and it's bad for getting details. The backlight is good because it can create siloutte if more light's coming from the background rather than it coming off the object. This can be bad for showing details, though.