Answer 1: Abacus is the first mechanical computing device developed by Chinese around 3000 to 4000 years ago.
It is made up of wooden rack that has metal rods.
Question 2:What is Napier’s bone?
Answer 2: Napier’s Bones was manually operated calculating device invented by John Napier.
The Napier’s bone consists of eleven sets of rods. Tens rods are carved with multiplication of numbers from 0 to 9 and one rod is carved with the numbers from 1 to 9.