The Plugin Site

I downloaded a plug-in for Photoshop with an extension = ???.atn
I like to use this plug-in in WebPlus 7.0 from Serif.
Somebody know how can I use this plug-in?
Thanks a lot.
Marco

That appears to be a Photoshop Action file. To the best of my knowledge, Photoshop is the only program that can use actions... sorry

Yes. that is an action file. Not the same thing as a plugin.