authentic
Pronunciation /ɔːˈθɛntɪk/
adjective
1 Of undisputed origin and not a copy; genuine.
1.1 Made or done in the traditional or original way, or in a way that faithfully resembles an original.
1.2 Based on facts; accurate or reliable.
1.3 (in existentialist philosophy) relating to or denoting an emotionally appropriate, significant, purposive, and responsible mode of human life.
2 Music
(of a church mode) containing notes between the final (the principal note) and the note an octave higher.
Compare with plagal
Origin
Late Middle English via Old French from late Latin authenticus, from Greek authentikos ‘principal, genuine’.
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You must be the judge, or rely on some "expert" to determine whether a digital artifact is
authentic and original to the site where you see it. Fortunately for you, the current writer is the "expert" and originator of both these explanatory words and the image in question. To be fair, you should know that this image is released using the creative commons CC0 "public domain dedication" What that will ultimately allow is way beyond the scope of the current discourse.

Words are a game. Sometimes I play alone, but I encourage YOU to play, too.