Research Into The Calculator

History of the calculator
The first electronic calculator was created in the 1960s. Pocket sized devices came available to buy in the 1970s. It was built on from a history of early maths instruments like the abacus (2000 BC) and the mechanical calculator (17th century). Before 1970, a more primitive form of calculator, the slide rule , was commonly used. It consisted of a slat of wood, called the slide, that could be moved in and out of a reinforced pair of slats. Both the slide and the outer pair of slats had calibrated numerical scales. A movable, transparent sleeve called the cursor was used to align numerals on the scales. The slide rule did not require any source of power, but its precision was limited.
The abacus is one one of the first forms of calculator and is still used in some regions of the Far East. The abacus uses groups of beads to denote numbers. Like the slide rule, the abacus requires no source of power. The beads are positioned in several parallel rows, and can be moved up and down to denote arithmetic operations. It is said that a skilled abacus user can do some calculations just as fast as a person equipped with a battery-powered calculator.


Calculators in Science
Calculator can perform addition, subtraction, multiplication and division. These four basic functions represent the heart of any calculator. A Scientific calculator uses these four functions to perform higher level functions such as roots, logarithms, trigonometric functions, and hyperbolic functions. Internally, some calculators actually perform all of these functions by repeated processes of addition.

Calculators in Popular Culture
Marty Mcfly wore a calculator watch in the 1980s film Back To The Future, which became very iconic as this was before the time mobile phones became small enough to carry. 



Mechanical and Electromechanical Calculators

Early devices used to aid in calculation include the abacus (still common in E Asia) and the counting rods, or "bones," of the Scottish mathematician John Napier. The slide rule, invented in 1622 by William Oughtred, an English mathematician, was widely used to make approximate calculations, but it has been replaced by the electronic calculator. In 1642, Blaise Pascal devised what was probably the first simple adding machine using geared wheels.

In 1671 an improved mechanism for performing multiplication by the process of repeated addition was designed by Gottfried W. von Leibniz. A machine using the Leibniz mechanism was the first to be produced successfully on a commercial scale; devised in 1820 by the Frenchman Charles X. Thomas, it could be used for adding, subtracting, multiplying, or dividing. A mechanism permitting the construction of a more compact machine than the Leibniz mechanism was incorporated into a machine devised late in the 19th cent. by the American inventor Frank S. Baldwin. Later the machine was redesigned by Baldwin and another American inventor, Jay R. Monroe. At about the same time, W. T. Odhner of Russia constructed a machine using the same device as Baldwin's. Charles Babbage, an English mathematician, and William S. Burroughs, an American inventor, also made important contributions to the development of the calculating machine.

Early mechanical adding machines were equipped with a keyboard on which numbers to be added were entered, a lever to actuate the addition process, and an accumulator to display the results. A full keyboard consisted of 10 columns of keys with 9 keys in each column, numbered 1 through 9. Each column could be used to enter a figure in a particular decimal place so that a number up to 10 digits long could be entered; if no key was pressed in a given column, a zero was entered in that decimal place. The lever was pulled in one direction when a number was to be added and in the opposite direction when it was to be subtracted. The accumulator was a set of geared wheels, each corresponding to a decimal place and having the digits 0 through 9 printed on its circumference. When a given wheel made a complete rotation, the next wheel was advanced by one digit. The mechanical adding machine remained essentially the same until the mid-1960s, with improvements consisting of motors to actuate additions and subtractions and mechanisms to print out results on a paper tape. 

Electronic Calculators

Electronic calculators, which became available in the early 1960s, at first were merely faster and quieter adding machines. The invention of the microprocessor and advances in integrated-circuit technology made small, but highly sophisticated, calculators possible, and by the mid-1970s they were in wide use. Simple calculators perform only the basic four functions of addition, subtraction, multiplication, and division. More sophisticated calculators can perform trigonometric, statistical, logarithmic, and other advanced calculations.

Some electronic calculators are actually small computers with limited memory and programming capabilities. Some of these programmable calculators can accept plug-in semiconductor memory cards or programming modules for special applications, such as financial calculations, unit, currency, or number-system conversions, or engineering calculations. Others are also available that include nonmathematical functions such as data storage and schedule organizing. The personal digital assistant, a hand-held device optimized as an organizer with communications capability and accepting handwritten input, is a bridge from calculators to full computer function.

Early electronic calculators had numeric displays made from light-emitting diodes (LEDs). They have been supplanted by liquid-crystal displays (LCDs), whose lower power consumption helps to reduce battery drain. Some calculators use an LCD readout to provide a graphic, as well as numeric, display. CMOS, or complementary metal-oxide-semiconductor (see integrated circuit), technology is also preferred for battery-operated models because of its low-power requirements. Some calculators are powered by solar cells in ordinary room light.