The "presets" correspond to a special setting in each of the 8 modules.

Once you've had created the good settings for a kind of photo, you'll have probably ro re-use it later. Save it under an explicit name by clicking the button
The next time you'll need those settings, select all the concerned photos, then click on your preset and on the button .

You can modify your preset at any time by clicking on . Change one or many settings, and then cvalidate with the button of the preset editor.