Form submit action file for DW

Hello. What kind of file is it asking for?
Also, the little ? in the upper right of this box pictured only goes to nothing.
If it's a javascript file, can someone link me to a template?
Thanks a bunch!
[Moved from the Lounge (which is where you can "connect with your peers" from across all of Adobe's products for conversations that don't directly relate to help and support) to a product-specific support forum - moderator]
