The Comptometer (7 h 50 m, 18 nov 2018 ano – 20 h 53 m, 30 jul 2019 ano)
Descrição:
The Comptometer was introduced in 1885, and it was the first mechanical calculator in which numbers were entered/processed by pressing keys. Making the operation of the machine easier.
Instead of having 10 keys for the numbers from 0 to 9, they had columns of 10 keys each, introducing successively . The most powerful calculators had up to 20 columns in their full keyboards.
Adicionado na linha do tempo:
Data:
7 h 50 m, 18 nov 2018 ano
20 h 53 m, 30 jul 2019 ano
~ 8 months