Lighting

Fill light

reduce contrast

Key light (main light)

main source of light

Hair light

A tool to light up your hair

Shadowless

having no shadow in the photo

Hard light

 direct lighting

Soft light

Indirect lighting 

Grey card

to reflect light for consistent exposure

Reflector

reflects light onto the subject

Diffuser

Something that spreads or reduces light

Intensity
the brightness of each lightsource

Direction: The point at where the light hits the subject
Intensity: The harshness or softness of the light
Color: 
Contrast: The balance between light and dark
Hardness: