I've been asked to write an article describing how to create actions, so here goes...

"An action is a series of commands that you play back on a single file or a batch of files." (Photoshop CS On-line Help)

I'm using as an example one of Scott Kelby's tips from The Photoshop Book for Digital Photographers (Amazon.com Amazon.co.uk), "Extreme Edge Sharpening" (pp 309). This is a well-known technique for sharpening images. The steps Scot describes are:

1. Select the entire image and copy it
2. Create a new alpha channel and paste the selection into the channel
3. Run Filter>Stylize>Find Edges
4. Adjust Levels
5. Apply Gaussian blur
6. Adjust Levels again
7. Load the alpha channel as a selection
8. Apply sharpening using Filter>Sharpen>Unsharp Mask

Some of these steps equate to a single command in Photoshop; others require multiple commands. Creating an action is simply a matter of recording the keystrokes and/or mouseclicks to perform the individual commands.

First some words about the Actions Palette (AP). This shows the action sets that are currently loaded in Photoshop: