Virtual Entity’s terminology:

soul = metadata set of a file
aura = space around the soul where file’s relations and user’s annotations are stored
substance = if a file is an ‘audio’, ‘video’, ‘text’ or ‘image’ file
twin = two files are twins when they have the same content in a different format or compression
parent = a file which was used in another file (also called ‘ancestor’)
child = a file which uses another file is a ‘child’ (or a descendent) of it
natural born digital = a file which was created inside a computer using material created inside a computer
natural born analogue = a file which was made using material that has an analogue relation with the real world, and a carrier
native file = the first copy (or original, it’s the same) of a file which reaches the Net.