COMPUTING DEVICES I (SS1 FIRST TERM)

 COMPUTING DEVICES I

(PRE – COMPUTER AGE TO 19TH CENTURY)

Abacus

Features and components

Abacus was invented around 500 BC. It was made up of strings or wires, frames and beads. Modern Abacus uses sliding beads in columns that are divided into two by a center bar. The upper part is called the heaven and each of the two beads (representing the two hands) is worth 5 when moved

to the center. The lower part is called the “earth”, where each of the 5 beads (representing the 5 fingers) is worth 1 when moved towards the center. The Abacus is really just a representation of the human fingers.

Use

For addition and subtraction

Napier’s Bone

Features and components

John Napier in 1617 invented the Napier’s bone. The device involves a collection of moveable numbered rods and a board.

Use

Used to perform multiplication

Slide rule 

    Features and components 

William Oughtred invented the slide in 1632. The Slide rule is a mechanical analog computer. In its most basic form, the slide rule uses two logarithmic scales to allow rapid multiplication and division of numbers.

Uses

The slide rule is used mainly for multiplication and division, and also for "scientific" functions such as roots, logarithms and trigonometry, but usually not for addition or subtraction.

Pascal’s calculator

Features and components

Blaise Pascal invented the Pascal’s calculator otherwise called PASCALINE in 1642. It is a gear or dial driven (just as that on analogue telephone) calculating device.

Use

It could only be used for addition and subtraction operations. It’s use is evident in odometer and electricity meter.

Leibniz multiplier

Features and components

Leibniz multiplier or (Stepped Reckoner) was invented by Gottfried William Leibniz in 1671. It was an improvement on the PASCALINE. It contains a special kind of gear called “Leibniz wheel”.

Uses

It could add, subtract, multiply and divide.

Jacquard’s loom

Features and components

In 1801, Joseph Marie Jacquard invented the Jacquard’s loom. This machine was controlled by a number of punched cards, put together into a continuous sequence.

Use

Used for producing fabrics with beautiful patterns

Difference engine

Features and components

In 1822, An English mathematics professor called Charles Babbage invented the Difference engine. It was composed of 25000 parts, weighed 15 tons and stood 8 feet (2.4m) high.

Use

Used for calculating differential equations.

Analytical engine

Features and components

In 1832, Charles Babbage designed another machine called Analytical engine which was deemed to be the first mechanical computer. The machine was steam-powered, though never completed, outlined the basic elements of a modern day general purpose computer. It contains input in the form of punched card containing operating instructions and a "store" for memory of 1,000 numbers of up to 50 decimal digits long. It also contained a "mill" with a control unit that allowed processing instructions in any sequence, and output devices to produce printed results. Augusta Ada, Countess of Lovelace (1815-1842) created the instruction routines to be fed into the computer, making her the first female computer programmer.

Use

It could store 1000 numbers of up to 50 decimal digits long. It was programmable.

Herman Hollerith machine

Features and components

Herman Hollerith invented the Herman Hollerith machine in 1890 which used punch card to store information which he fed into the machine to compile the results mechanically.

Use

It was used for collating, sorting and summing the data gotten from 1890 US census.

Burrough’s Machine

In 1885, William Seward Burroughs from American Arithmometer Company invented this mechanical adding machine. The early Burroughs models were large machines characterized by having glass panels in the sides, so the mechanism could be seen. Common components of the Burroughs machine: keypads, Levers, Registers, and Printer.