Light
Light determine the shading of an object and the shadows it cast. As such, they are fundamental part of graphical rendering.

Type, the current type of light
Range, defines how far the light emitted from the center of the object travels (Point and Spot light)
Spot Angle, defines the angle at the base of a spot light cone (Spot light)
Color, uses the color picker to set the color of the emitted light
Mode, specifies the Light Mode used to determinate if and how a light is "baked"
Intensity, sets the brightness of the light. The default of Directional is 0.5, for Point, Spot and Area is 1
Indirect Multiplier, use this value to vary the intensity of indirect light, that is the light bounced from one object to another.
Shadow Type, determines whether this light casts hard shadows, soft shadows or no shadows at all
Baked Shadow Angle, if light is Directional, mode is Baked and shadow is Soft Shadows, this property adds some artificial softening to the edges of shadows
Baked Shadow Radius, if light is Point or Spot, mode is Baked and shadow is Hard or Soft Shadows, this property adds some artificial softening to the edges of shadows
Realtime Shadows, if mode is Realtime and shadow is Hard or Soft Shadows, this properties allows to control realtime shadow rendering
Strength, controls how dark the shadows cast by light are, 1 to 0, default 1
Resolution, controls the rendered resolution of shadow maps, a higher value more impact to the GPU
Bias, controls the distance at which shadows are pushed away from the light, 2 to 0, default 0.05
Normal Bias, controls the distance at which the shadow casting surfaces are shrunk along the surface normal, 3 to 0, default 0.4
Near Plane, controls the value for the near clip plane when rendering shadows, 10 to 0.1, default 0.2
Cookie, specifies a texture mask through which shadows are cast
Draw Halo, draws a spherical Halo of light with a diameter equal to the range value
Flare, you can set a Flare to be rendered at the light position by placing an Asset in this field to be used as its source
Render Mode, sets the rendering priority of the selected light. Can affect lighting fidelity and performance
Auto, the rendering method is determined at runtime, depending on the brightness of nearby lights and the current Quality Settings
Important, the light is always rendered at per-pixel quality, this is used only for the most noticeable visual effects
Not Important, the light is always rendered in a faster vertex/object light mode
Culling Mask, selectively exclude groups of objects from being affected by the light
Different types of light emit their assigned color in different ways.