Photoshop Action File
Photoshop Action File (also called Photoshop Actions File) is file format associated with Adobe Photoshop. It apparently stores a set of macros.
The format has a lot in common with PSD format, and uses many of the same data structures.
The known versions of the format begin with bytes (hex)
00 00 00 10, followed by a field that almost certainly starts with
There is evidence that other versions exist.