1. History of Calculator
By Kyumin (Louis) Kim

2. Before Calculators
In 2000 BC, the Sumerians and Egyptians used the Abacus, bones to tally items, and pebbles and counting boards.

3. The Start OF Calculators: Calculating Machines in 1640’s
The first calculating machines were made by Blaise Pascal in 1649.
Blaise Pascal was the first to receive a patent which was the Royal Privilege.
He was granted exclusive rights to make and sell the calculating machines in France.

4. First commercially successful Calculating machine
About 170 years later, the first commercially successful calculating machines was the Arithmometer. The Arithmometer was allowed to sell from 1820 by Thomas de Colmar.

5. Early electronic calculators
The Casio Computer Company’s Model 14-A on the right was released in 1957.
Early electronic calculators were desk-size, built with vacuum tubes and later with transistors.

6. Texas instruments company
In 1958, Texas Instrument engineer Jack Kilby made the first working integrated circuit.
After 9 years, Texas Instrument engineers made the first handheld electronic calculators.

7. Programmable calculators
In 1974, HP-65 was the first pocket programmable calculator.
Later on, more efficient programmable calculators were on sale.

8. Calculators allowed in schools
In the 1970’s, calculators were brought to classrooms.
According to Science News articles, in 1975, 1 in 9 people had calculators.
Connecticut was the first state to require calculators.

9. Calculators in 2015
Now, most countries make students use calculators for studying.
The invention of calculators made our lives much more convenient.

10. References: https://www.wikiwand.com/en/Calculator
Images:
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