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A calculator is just like a computer. For each button you push, it sends the binary through wires and processes it into the numbers you see on the screen. For example, if you made the number 23 on the calculator, it would send the binary number 00010111 through the wires and process the number to the screen.
HISTORY OF CALCULATORS
One of the first calculators was called the abacus. This was a non-electric calculating device based on the positions of two sets of beads moving on strings.
Calculator Time-Line
1620 The abacus was developed
1623 The first mechanical calculator was developed
1961 The first electronic desktop calculators was developed
1965 The first hand-held electronic calculators was developed
1969 The first battery powered, hand-held electronic calculator was developed
1978 The first solar-powered and first credit-card size calculator was developed
1980 The first hand-held computer was developed
Present New ideas continue to be developed and improvements are made all the time on the calculator
How does a calculator work?
Calculators use math that is easy compared to the math we learn in school. For instance, we learn that 2 + 5 = 7, 3 + 6 = 9, 8 + 3 = 11 etc. Our math is based on the number 10. That means, that when we say 23 we are actually saying there are 2 tens and 3 ones. We base our numbering system on 10’s because we have 10 toes and 10 fingers and that was what we used when people started counting. Calculators don’t have fingers and toes and so instead they change voltage levels by turning the voltage on and off. These two levels, on and off, are what the calculator uses in its math. We call the “off” level 0 and the “on” level 1. We can represent any number with binary numbers. Decimal numbers are shown by hundreds, tens, and ones; binary numbers are shown by eight’s, four’s, two’s, and one’s. Therefore, 13 is shown by 1 eight, 1 four, and 1 one. Seven is shown by 1 four, 1 two, and 1 one. Nine is shown by 1 eight and 1 one. Here is how a calculator works. Let’s say you want to add 9 + 4. As we know, the answer is 13, but here is how a calculator works the problem:
Eights fours twos ones
1 0 0 1
+ 0 1 0 0
------------------------------
1 1 0 1
So, a calculator works by changing decimal numbers to binary, doing binary math on the binary numbers and changing the answer to decimal numbers that people can understand.
