Pre-mechanical Period, The Mechanical Period, The Electromechanical Period,The Electronic period, The Four Generations of Digital Computing - (Joannacel A. Paraiso)

I learned about the four basic periods in the history of computers. The:
· Pre- mechanical Period(3000-1450)
· Mechanical Period(1450-1840)
· Electromechanical Period(1840-1940)
· Electronic Period(1940- present)

In the Pre-mechanical Period, I learned that:

· Petroglyths are signs or simple figures carved in rocks.

· Pictographs are the pictures or sketches that visually resemble
that which is depicted.

· Ideographs are the symbols to represent ideas or concepts.

· Computing began when our ancient ancestors devised the first, rudimentary
counting methods.

· In 3100 B.C., the Sumerians in Mesopotamia(southern Iraq) devised cuneiform—
the true first written language and the first real information system.

· The Phoenicians created symbols that expressed single syllables and consonants
(the first true alphabet).

· The Greek adopted the Phoenician alphabet and added vowels.

· The Romans gave the letters Latin names to create the alphabet we use today.

· In Egyptian system. 1-9 as vertical lines, the number 10 as a U or circle, the number 100as a coiled rope, the number 1000 as a lotus blossom, 10000 as a finger, 100000 as a frog and 1000000 as an Egyptian.

· The first numbering system similar to those we use today were invented by the Hindus in India who created a nine- digit numbering system.

· Around 875 A. D., the concept of zero was developed.

· Abacus is the first calculator and it is also one of the very first information processor.

The Mechanical Period
> Johann Gutenberg invented the movable- type printing process.

>The people who held the job title computer are the one who works with numbers.

>John Napier introduces logarithms. Logs allow multiplication and division to be reduced to addition and subtraction.

>Wilhelm Shickard invents the first mechanical calculator. It can work with six digits, and carries digit across columns. It works but never makes it beyond the prototype stage because it was burned.

>William Oughtred invented the slide rule and an early example of an analog computer.

>Blaise Pascal invented the mechanical calculation machine. He called it Pascaline. It is made out of clock gears and levers and could solve basic mathematical problems.

>Gottfried Wilhelm von Leibniz invented the machine called stepped reckoner that could multiply 5 digit and 12 digit numbers yielding up to 16 digit number.

>Joseph- Marie Jacquard developed an automatic loom that was controlled by punch cards.

>Arithmometer became the first mass- produces calculator developed by Charles Xavier Thomas De Colmar. This device performed the same type of computations as Leibniz’s stepped reckoner, but was more reliable.

>Charles Babbage invented the first modern design: a steam- powered adding machine called the difference engine. He also invented the analytical machine that took information from punched cards to solve and print complex mathematical operations. The difference engine and the analytical engine are regarded as the first “thinking machines”. These machines were made for people who weren’t math experts. The engines are easy to operate and produced solutions at the turn of a hand crank. He earned the title “father of computers”.

>Ada Augusta Lovelace was credited the “first computer programmer”. The programming language Ada is named in her honor.

The Electromechanical Period

Voltaic Battery
>The first electric battery, known as the voltaic pile was invented by Alessandro Volta. It is consisted of a stack of alternating discs of zinc and copper or silver separated by felt soaked brine. They provided a simple source of stored electrical energy that didn’t rely on mechanical means.

Telegraph>Invented by Samuel F. B. Morse.

Telephone and Radio
>Developed by Alexander Graham Bell. The first and the famous quotation that was transmitted in the first telephone was “Watson, come here, I want you”.

>Guglielmo Marconi discovered that electrical waves travel through space and can produce an effect far from the point at which they originated.

>George Boole develops binary algebra known as Boolean algebra.

>Pehr and Edvard Schuetz complete their computing machine capable of processing fifteen- digit numbers, printing out results, and rounding off to eight digits.

>Dorr Felt devises the Comptometer.

>Herman Hollerith was the first person to successfully use punched cards.

>Otto Shweiger invented the first efficient function calculator called the millionaire.

>Lee De Forest developed the vacuum tube.

The Electronic period
. The first programmable computer is the Z1 created by Konrad Zuse.
· The first digital computer is the Atanasoff-Berry Computer(ABC).
· The first stored program computer is the EDSAC.
· The first personal computer is the Altair 8800.
· The first workstation is the Xerox Alto introduced in 1974.
· The first laptop or portable computer is the Osborne I.
· The first PC (IBM compatible) computer is the IBM PC.
· The first PC clone is the Compaq Portable.
· The first Apple computer is the Apple I.
· The first computer company is the Electronic Controls Company.
· The first multimedia computer is the amega.
. Other major computer companies first are the Compaq Digital, Del, Hewlett Packard, NEC, and Toshiba.
The Four Generations of Digital Computing
First Generation
>The computers had vacuum tubes, resistors, and welded metal joints.

Second Generation
>Uses transistors as main logic element.

Third Generation
>Individual transistors were replaced by integrated circuits.

Fourth Generation
>Uses microprocessor. It is an integrated circuit built on a tiny piece of silicon.