We underestimate the computing power of a device that can fit in the palms of our hands. Nowadays, for many people, calculator is an application that open on their smart phones. But before it got that luxurious, calculators went through a series of evolutionary steps that brought us to this point.
The history of the calculator, or what we know of it, began with the hand operated Abacus in Egypt in 2000 BC. The Abacus is a rectangular frame with horizontal rods. On each rod, there is a certain number of beads that can slide across. These beads represent tens, hundreds and thousands.
Mechanical calculators came out around 1642 when Blaise Pascal created a device that could perform arithmetic operations with two numbers. The Arithmometer was then upgraded and improved all the way till 1887 when Dorr. E. Felt’s patented the Comptometer. The Comptometer had push keys similar to our modern day calculators. However, it was much larger than pocket size.