As explained here, it turns any file into a template. Tick it and open the file, and a copy of the file will be created, ready to be saved elsewhere without affecting the original.
What is the 'Stationery Pad' setting in OS X Finder?
As explained here, it turns any file into a template. Tick it and open the file, and a copy of the file will be created, ready to be saved elsewhere without affecting the original.