This is where you can modify the low and high lights like Shadow / Highlight in Photosop. The settings can be very subtle by using the Gine settings. I prefer to use this option in Photoshop after processing in DxO Optics.

Let's try the Lighting module.

On the right, different values for the lighting had been appplied to the RAW file. Notice that the highlights (near the lights) aren't modify. Only the low lights are enhanced. That's essential when you want to lighten a picture without bruning the light areas.

On the right: RAW file developed with different Lighting values.
Canon 350D + Sigma 18-50 at 18 mm open at 2.8 on a tripod. 30 s at 800 ASA.