Definition
Tone mapping a a digital photo editing technique that maps a color or brightness to another to reduce the image's [[dynamic range]].
It consists in mapping extreme values of brightness to less extreme values, so that a screen can display it without reaching its own brightness limits.
Inverse tone mapping is the opposite : it boosts contrast by exaggerating the dimmest and brightest areas in the final image.
==The “Contrast” in photo editing software is tone mapping with a default curve.
Tone mapping allows more control by selectively altering the image’s areas.==
Adobe Lightroom's sliders for shadows and highlights are tone mapping.