A Panels are the different sets of controls you can see appear on the left hand side of the screen such as Home, Crop, Red Eye etc.
Home Panel is the first panel you will see. This is the panel that is returned to after making a change to your photo.
History lists all the different changes you have applied to your photo. You can go back and edit anything in the history at any time.
Stages are the individual items within the history
Effects appear as a Stage in the history
Remove Objects Tool is a panel for removing objects in your photo
Select Area Panel is a panel for selecting parts of your photo to be modified by effects
Gallery is a panel for browsing the library of effects
Red eye Tool is a panel for removing red eye
Crop Tool is a panel for cropping images
Straighten Tool is a panel for straightening images
Tone Sliders is a panel for quickly performing adjustments to the whole image

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