If you can translate from A to B and from B to C can you translate from A to C without learning the translations directly? Well yes you can. So the translate AI has created its’ own language B (we think) that can function as a midpoint between not only A and C, but also D,E,F, etc.
Would it be what Esperanto wanted to be?

Source: Google’s AI translation tool seems to have invented its own secret internal language | TechCrunch