In CMYK, K doesn’t stand for a Black!
We all know that CMYK is the color mode used for color printing. But what most of us don’t know is that in CMYK, K doesn’t stand for Black, K stands for Key. CMYK is Cyan, Magenta, Yellow, and Key (Key Plate/ Key Color).
Then what is Key (Key plate)?
As per Wikipedia...
In printing, a key plate is a plate that prints the detail in an image.[1]
When printing color images by combining multiple colors of inks, the colored inks usually do not contain much image detail. The key plate, which is usually impressed using black ink, provides the lines and/or contrast of the image. However, in two-color separations where neither color is black, the darker of the two colors may be considered the Key Plate instead.
In short, Key plate is the plate which provides the maximum details of the image. While printing, Cyan, Magenta and Yellow plates are properly aligned with this key plate.
In the modern printing world, the key plate is usually inked using black color but before that, it was never the same. Other colors like Brown and Blue were used as well to an impressed key plate. But over the years, Black became the mainstream color for key plates.
And because the black color and key plate became the usual affair, people started referring K in CMYK to the black color. Theoretically and practically it is not true.
Companies like Adobe use their own color profiles. So, any desktop application software which uses the CMYK color mode, K stands for BLACK.
Conclusion
So in the printing domain, CMYK is Cyan, Magenta, yellow and... Key, of course !! 😛
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