There are a range of adjustments which can be applied to your design as a new layer for creative or corrective purposes.
Adjustments are applied from the Layers panel and most include customisable settings alongside general adjustment options. Once applied, they can be identified as both an adjustment and a specific adjustment type by using unique symbols.
Adjustments can be symbolised, i.e. their settings can be updated across multiple instances of the adjustment layer at the same time.
Adjustment layers only affect objects in the layer which are below them. Alternatively, you can make an adjustment a child of an object, thereby affecting that object only.
Some adjustments (i.e., Curves, Levels, or Channel Mixer) can be made in any colour space independently of the document colour space.
The following general settings are available from all adjustment dialogs: