Action types

You can assign the following actions to links, bookmarks, pages, media clips, and form fields:

Execute A Menu Item
Executes a specified menu command as the action.

Go To A 3D View
Jumps to the specified 3D view.

Go To A Page View
Jumps to the specified destination in the current document or in another document.

Import Form Data
Brings in form data from another file, and places it in the active form.

Open A File
Launches and opens a file. If you are distributing a PDF file with a link to another file, the reader needs the native application of that linked file to open it successfully. (You may need to add opening preferences for the target file.)

Open A Web Link
Jumps to the specified destination on the Internet. You can use http, ftp, and mailto protocols to define your link.

Play A Sound
Plays the specified sound file. The sound is embedded into the PDF document in a cross-platform format that plays in Windows and Mac OS.

Play Media (Acrobat 5 Compatible)
Plays the specified QuickTime or AVI movie that was created as Acrobat 5-compatible. The specified movie must be embedded in a PDF document.

Play Media (Acrobat 6 And Later Compatible)
Plays a specified movie that was created as Acrobat 6-compatible. The specified movie must be embedded in a PDF document.

Read An Article
Follows an article thread in the active document or in another PDF document.

Reset A Form
Clears previously entered data in a form. You can control the fields that are reset with the Select Fields dialog box.

Run A JavaScript
Runs the specified JavaScript.

Set Layer Visibility
Determines which layer settings are active. Before you add this action, specify the appropriate layer settings.

Show/Hide A Field
Toggles between showing and hiding a field in a PDF document. This option is especially useful in form fields. For example, if you want an object to pop up whenever the pointer is over a button, you can set an action that shows a field on the Mouse Enter trigger and hides a field on Mouse Exit.

Submit A Form
Sends the form data to the specified URL.

Source: Adobe