Calculator

A calculator is a device designed to perform mathematical operations such as addition, subtraction, multiplication, and division. Modern calculators are electronic and have buttons for entering numbers and a display to show results. They exist in various forms: handheld models, desktop models, and software versions built into computers and smartphones.

The word 'calculator' was also historically used for a person who performs calculations, but today it typically refers to the device itself. The distinction between a calculator and a computer lies in the scope of tasks each can perform: a calculator focuses on mathematical operations, while a computer is a general-purpose device capable of many different tasks.

Brief history

Before electronic devices, people used tools such as the abacus, which was employed for many centuries. In the seventeenth century, mechanical machines were invented with gears and springs that could add and subtract numbers. During the nineteenth and early twentieth centuries, mechanical desk calculators became widespread in offices and banks.

The development of the transistor and later the integrated circuit made it possible to produce small, battery-powered calculators. From the 1970s onward, prices fell sharply and use became widespread, which led to the decline of mechanical calculators and logarithmic slide rules.

Types

The standard calculator performs the four basic operations and sometimes percentages and square roots. The scientific calculator adds trigonometric functions, logarithms, and exponents. The graphing calculator displays equations visually on a large screen in the form of graphs and mathematical curves. There are also financial calculators designed for interest and debt calculations.

Structure and operation

An electronic calculator consists of buttons, a small processor, memory, and a display. Most displays use LCD technology, which reduces power consumption. Many calculators run on batteries, while some have solar cells. Numbers are stored internally in binary code and converted to decimal format for display to users.

Educational use

Some schools and examinations restrict which types of calculators may be used, to ensure that students learn to do mathematics by hand. Debate continues about the impact of calculators on students' mathematical skills, and educational policies vary from country to country.