# Components of color space
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There are four components to color space:
+ The specific *color space* that applies to the video content. The color space specifies a range of pixel colors that can apply to the content.
+ The *color space metadata*, which identifies the color space being used. If this metadata is present, the content is said to be *marked* for a color space. 
+ The *brightness function* that applies to the color space. The brightness function controls the brightness of each pixel. The brightness is also known as gamma tables, electro-optical transfer function (EOTF), and transfer function. 
+ The *brightness metadata*, which identifies the brightness function being used.
+ The *display metadata * that applies to the color space. Not all standards have this metadata.

The video might use a specific *color space* and a specific *brightness function*. The video might also carry *color space metadata *that describes aspects of the color.