The definitions used here are from the Photoshop help files, with a few bits of added explanation here and there.
The Blend Modes control how pixels in two separate layers interact with and effect each other. It’s helpful to think in terms of the following colors when visualizing a blending mode’s effect:
* The base color is the original color in the bottom layer.
* The blend color is the color being applied by the upper layer.
* The result color is the color resulting from the blend.
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