And of course there's the joke of Standard vs Experimental gliders, such as the ASW-27. Looking on the FAA database, first thing is that there are 3 manufacturer/model codes containing 3, 5, and 73 gliders for a total of 81. Of these, there are 47 Standard, 21 Experimental, and 14 Unknown (Experimental?).

Beyond paperwork, there's no difference between Standard and Experimental (except for a few customized ones). Gotta love FAA and consistency.