Create action

An action is a series of commands that you play back on a single file or a batch of files.

For example, you can create an action that applies an Image Size command to change an image to a specific size in pixels, followed by an Unsharp Mask filter that resharpens the detail, and a Save command that saves the file in the desired format.
Most commands and tool operations are recordable in actions. Actions can include stops that let you perform tasks that cannot be recorded (for example, using a painting tool).
Actions can also include modal controls that let you enter values in a dialog box while playing an action.

To use the Actions palette
You use the Actions palette to record, play, edit, and delete individual actions. This palette also lets you save and load action files.

Photoshop Actions palette

A. Action set
B. Action
C. Recorded commands
D. Excluded command
E. Modal control (toggles on or off) 
To display the Actions palette, choose Window > Actions.
To expand and collapse sets, actions, and commands, click the triangle to the left of the set, action, or command in the Actions palette. Alt-click (Windows) or Option-click (Mac OS) the triangle to expand or collapse all actions in a set or all commands in an action.
To display actions as buttons (Photoshop), choose Button Mode from the Actions palette menu. Choose Button Mode again to return to list mode. You can’t view individual commands or sets in Button mode.
To select actions in the Action palette, click an action name. In Photoshop, Shift-click action names to select multiple, contiguous actions and Ctrl-click (Windows) or Command-click (Mac OS) action names to select multiple, discontiguous actions.

Action palette looks like this....

Photoshop actions can make your life much easier if you know how to use them.
There are many free Photoshop actions on the internet today and we will learn how to make our own actions instead of doing the sameboring work repeatedly.

• How to Create Your Own Photoshop Action