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Calculator

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A calculator is a portable electronic device designed to perform mathematical calculations. These tools range from simple devices for basic arithmetic to complex machines for advanced mathematics.

Casio calculator JS-20WK in 201901 002
Casio calculator JS-20WK in 201901 002

While basic models handle addition and subtraction, specialized versions exist for specific fields. Scientific calculators can process trigonometric and statistical data. Graphing calculators can even plot functions in higher-dimensional Euclidean space. In the modern era, dedicated hardware is often replaced by software on smartphones and tablets.

Precise Calculator Pi 20210113
Precise Calculator Pi 20210113

To understand how a calculator works, we must look at its internal components. The process begins with a scanning unit, which is a part of the software that constantly polls the keypad. When you press a button, the scanning unit detects an electrical signal. This signal is then encoded into binary-coded decimal (BCD) format. This specific way of representing numbers makes it much easier for the hardware to display digits on a screen.

Interior of a calculator
Interior of a calculator

Once a number is entered, it is sent to the X register, which is a type of temporary memory. If you enter a second number, the first number is pushed into the Y register. At the same time, the math command, such as multiplication, is stored in a flag register. This flag tells the processor which operation to perform. The Arithmetic Logic Unit (ALU) then takes the numbers from the X and Y registers. The ALU executes the instructions using programs stored in the permanent, non-volatile memory, known as ROM.

Interior of a calculator
Interior of a calculator

Calculators are categorized by their complexity and intended use. Basic calculators are often inexpensive and may only store one number at a time. More advanced models use variables to store many different numbers in the user memory, or RAM. These variables are often named "ans" or "ans(0)". Some high-end models allow for extended memory through an array index.

Fx-991EX
Fx-991EX

Printing calculators are another distinct type, featuring a unit that prints results onto paper rolls.

Tischrechner Walther ETR2034S resized
Tischrechner Walther ETR2034S resized

The history of calculating tools spans thousands of years. Humans once used bones, pebbles, and the abacus to assist with counting. In the 17th century, mechanical calculators were invented by Wilhelm Schickard and Blaise Pascal. Pascal developed his machine to help with the heavy math required for tax supervision. The electronic era began in the early 1960s with the first solid-state calculators. A major turning point occurred in the 1970s with the development of the Intel 4004. This was the first microprocessor, created for the Japanese company Busicom.

17th-century-mechanical-calculators
17th-century-mechanical-calculators

Technological shifts have changed how much of the world's computing power calculators represent. In 1986, calculators accounted for an estimated 41% of the world's general-purpose hardware computing capacity. By 2007, this share had dropped significantly to less than 0.05%. This decline happened as computing power moved into more versatile devices.

HP-65 white background
HP-65 white background

Despite this, hardware calculators remain vital in many educational and professional settings.

Modern calculators use various methods to power their circuits and show information. Most pocket models use batteries or solar cells for energy.

Solar-calculator
Solar-calculator

Older or larger desktop models may connect to mains electricity. For the display, most current devices use liquid-crystal displays (LCDs). These have largely replaced older technologies like light-emitting diodes (LEDs) or vacuum fluorescent displays (VFDs).

LED DISP
LED DISP

While basic displays use seven segments to form digits, advanced models may use a dot-matrix display for more complex visuals.

Fx-991EX
Fx-991EX
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🖼️ Images & Media (19)
File:Casio calculator JS-20WK in 201901 002.jpg
Casio calculator JS-20WK in 201901 002.jpg
File:Fx-991EX.jpg
Fx-991EX.jpg
File:CalculatorFractions-5550x.jpg
CalculatorFractions-5550x.jpg
File:Interior of a calculator.jpg
Interior of a calculator.jpg
File:Tischrechner Walther ETR2034S resized.jpg
Tischrechner Walther ETR2034S resized.jpg
File:17th-century-mechanical-calculators.jpg
17th-century-mechanical-calculators.jpg
File:Grant mechanical calculating machine 1877.jpg
Grant mechanical calculating machine 1877.jpg
File:EdithClarkeCalculatorUSPatentDrawing.png
EdithClarkeCalculatorUSPatentDrawing.png
File:LED DISP.JPG
LED DISP.JPG
File:Elka-22 (I197211).png
Elka-22 (I197211).png
File:Olivetti Programma 101 - Museo scienza e tecnologia Milano.jpg
Olivetti Programma 101 - Museo scienza e...
File:Casio as-a ckt1 1c.jpg
Casio as-a ckt1 1c.jpg

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