the someone who told you was right, FFF and FDM refer to the same thing. The former stands for “Filament Fused Fabrication” and the latter for “Fused Deposition Manufacture” (or slight variations thereof, depending on who you ask). Which one of these abbreviations is registered or not, I don’t know, but FDM is the more common one.
I also was a bit confused by this as saw in the XYZ CES 2016 press releases using the term FFF.
Apparently FDM is a Stratasys trademark, therefore the term Filament Fused Fabrication is just a different term for the same manufacturing process. So non-Stratasys printers are using the term FFF.
As Billie and Jie said FFF is for Filament Fused Fabrication which is not legally encumbered, FDA (Fused Deposition Modeling) is a trademarked term both terms means the same technology so do not worry about using both. info form make magazine: http://makezine.com/2011/11/30/sweet-fdmfff-3d-printed-wargaming-minis/ 4