Describes a color space that can be defined using the full gamut of human vision, as defined by a standard observer, independent of the color-rendering capabilities of any specific device.
In 1976, a group of scientists defined a color space that is not tied to a particular device so it is both consistent and measurable - this is known as the L*a*b* color space and it is currently the standard method for converting a color between RGB and CMYK. Because the L*a*b* color space does not relate to a particular device, it is known as a "device-independent" color space.
3D Representation: 
The L*a*b* color space has three different axes - L*, a*, and b*.
L* refers to the "lightness" of a color - this value ranges from 0 (no lightness) to 100 (maximum lightness).
The a* axis determines the red-to-green hue of a color - this value ranges from +128 (red) to -128 (green).
Finally, the b* axis defines the yellow-to-blue hue of a color - this value ranges from +128 (yellow) to -128 (blue).
2D Representation:
See Color Management.
See Device - Dependent Color Space.
