QUIPU
Quipu was not invented by the incas to copy spoken language but rather to do things that spoken language failed to do. The quipu was first used around the 25th century B.C. it consisted of a combination of different cords, colors and knots that allowed them to record enormous amounts of mathematical data such as cosmic events, economics or census. Most importantly it allowed them to do basic operations that they would never have been able to do without this ancient accounting too, such as multiplications, additions, divisions and subtractions.
The key feature in my opinion is data materialisation. We have always been able to communicate and transfer information from one to another for millennia, but suddenly using the quipu, humans were able to take information from their heads, process it and record it through reliable objects that can be preserved for longer than any idea in a brain.
