Color Space

A color space is a method by which  we can specify, create and visualize colors. As humans we may define a color by its attributes of brightness, and colorfulness. A computer may describe a color using the amounts of red, green, and blue phosphor emission required to match a color. A printing press may produce a specific color in terms of the reflectance and absorbance of cyan, magenta yellow, and black inks on the printing paper.

sRGB

Smaller Red-Green-Blue. It is the mixtures of these colors that you see on your computer. Only used in web which has smaller color space.

Adobe RGB 1998

Adobe RGB color space was designed to encompass most of the colors achievable in CMYK color printers by using  RGB primary colors on a device such as the computer display. It encompasses roughly 50% of the visible colors specified by the Lab color space.

Lab Color Space

Lab color space is a color-opponent space with 3 channels. L is the lightness channel and if you adjust only the lightness in the image not its color. The a channel contains color information for green and magenta in the image. The b channel manages the blue and yellow colors in the image. It is device independent.

ProPhoto RGB

ProPhoto color space covers the largest range of colors and even goes beyond our eyes can see.

CMYK

Cyan-Magenta-Yellow-Black. The colors use for printing.

Good design 4 Basic Principles

Contrast size, thickness
Repetition unity
Alignment visual connection
Proximity distance

Sources:

http://www.myphotocentral.com/articles/choosing-color-space-srgb-adobe-rgb-prophoto/

http://en.wikipedia.org/wiki/Lab_color_space

http://en.wikipedia.org/wiki/Adobe_RGB_color_space

Colour Space Covension

by Adrian Ford and Alan Roberts

http://www.poynton.com/PDFs/coloureq.pdf