The history panel records the steps you take in your active document during a work session. Each document has its own history record.

To turn on the History Panel, Click on Window...History Panel on the Menu bar.

As you make changes to the open document, you will see the record of each action you make. Each action in your document creates a new action in the panel. You can go back in time and undo a step. Just slide the slider back to undo an action. To redo the undo, just click the Replay button.

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