That was English - each word is defined in any decent English Dictionary, so what do you not understand?
In #1 can you see the differences between the Pre and Post side-by-side comparisons?
You should see 3 changes: the white door had gone to grey, the iPad has been toned down and the side of the bag has been lightened. Each is a separate and independent non-destructive edit, which does not affect the image globally. They can also be undone.
#2 shows 2 "Teal Overlays" which define a region or local selection (i.e. part of the image) showing where I would like to make a Local change, limited to the region defined by the Selection.
#3 shows just one of these Selection Masks and a series of associated Sliders which can be dragged Up/Down to apply a change to the Local region defined by the Teal overlay mask. This change will not be applied to the other parts of the image.
#4 illustrates that I have applied 3 individual Masks, each a separate entity, so I can apply specific changes to each of the 3 Masked regions independent of each other or the rest of the image.
In #4, the Masks are not shown, just the control points that define them.
In #2 and #3 the Masks are shown as Teal overlays so you can see where each effect will be applied.
In the post, I am showing what I was able to achieve just after a few minutes of playing with DxO PhotoLab, having previously used the Nik Software which used the same technology. I understand that this is a significant change; introducing (multiple) Local Edits as opposed to Global Edits.
Hope that clarifies some stuff for you, if not, head over to the DxO website.
Thanks. I am lazy. I'd prefer to light properly before releasing the shutter.