Action animations are used to animate bones within an armature object. These animations are typically created in the "Pose Mode" of Blender's 3D view, in conjunction with Blender's "Action Editor" window.

Creating a new action animation

In Blender's 3d view, select the armature which you wish to animate:
With the armature selected in the 3d view, click the "Action Selector" pulldown in the header of the action editor window, and click "Add New":
The new Action (with a default name of "Action") should then appear in the pulldown:

Note: If actions have already been created, the "Add New" menu option will copy the currently active action and append a number onto the end of its name, for example "Action.001". To get a clean, blank, new action, delete all of the channels and keyframes from the copied action and optionally rename it to whatever you'd like.

For more information on working with the action editor window, see:

Adding bone keyframes to an action animation

Action animations are used primarily to hold keyframes for Blender's armature bones. Keyframes for Blender's bones are created with the "Pose Mode" of the 3d view.

Note: It is recommended that all bones be keyed into their desired positions at the start and end of each action animation. This prevents unwanted transforms carrying over from other actions when the actions are laid out sequentially as action strips on the NLA timeline.

For detailed information and instructions regarding creating action animations for armatures, see the following links

See Also:

jsgreenawalt.com

Blender DTS Exporter Documentation

Creating an action animation

Creating a new action animation

Adding bone keyframes to an action animation