What is an action?

Very simply, an action is one or more Photoshop operations that are recorded and then played back. The No. 1 reason to create and use actions is to work more quickly. An action can be very simple (one step) or very complex with multiple steps. You can create actions that are fully automatic, requiring no interaction, or an action that has many steps that require the users' input. Actions can easily be shared between Photoshop users (Macintosh and Windows), should you create an action that would be useful for your friends and colleagues.