Adobe PHOTOSHOP 6.0 Manual page 25

Undo the last performed operation
reverse the effect of the last operation. Most, but not all, operations can be reversed this way.
If you need to undo more than one operation, choose Window > Show History
Undo multiple operations
to display the History palette. This palette lists all the different states that the image has undergone as a
result of the recent edits you've made. To revert the image to a previous state, click the name of the state in
the History palette.
History palette
To automatically apply a sequence of operations to your image, choose
Automate repeated tasks
Window > Show Actions to display the Actions palette. This palette includes a default list of common
tasks, or actions. You can perform a desired action automatically by selecting it and clicking the Play
button ( ) at the bottom of the Actions palette. Or, you can record your own sequence of operations as a
stored action in the palette for future playback on a single image or batch of images.
If you make a mistake while working, simply choose Edit > Undo to
Playing an action
ADOBE PHOTOSHOP 6.0 15
User Guide