PRE-MECHANICAL AGE
It is generally regarded as having lasted from the beginning of recorded history to about the middle of the 15th century.
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| Control of fire |
Important advanced of the age:
- Control of fire - 500,000 BC
- Domestication of animals - 12,000 BC
- Domestication of plants - 800
Most used materials in this age:
- Ceramic - 7,000 BC
- Copper - 4,000 BC
Advances in writing during Pre-mechanical Age:
- First humans communicated only through speaking and picture drawings.
- 3,000 BC - Sumerians in Mesopotamia devised cuniform writing.
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| Cuniform Writing |
- About 2,600 BC - Egyptians write on the papyrus plant.
- 2,000 BC - Phoenicians created symbols.
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| Phoenician Alphabet |
- Around 600 BC - Greeks began to fold sheets of papyrus vertically into leaves and bind them together.
- Greeks later adopted the phoenician alphabet and added vowels; Romans gave the letters latin names to create the alphabet we use today.
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| Greek Alphabet |
- Around 100 AD - Chinese made paper from rags.
Advances in numbers during Pre-mechanical Age:
- 100 - 200 AD - The first numbering systems similar to those in use today were invented by Hindus who created a nine-digit numbering system.
- Around 875 AD - the concept of zero was developed.
- The abbacus is a tool that consisted originally of strings and pebbles, althought those used today in the teaching of basic mathematics are made from wooden formations. The tool is believed to have ariginated from China.
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| Ancient Abbacus |
MECHANICAL AGE
Mechanical Age developed between 1450 and 1840, when the inventors began to use tecniques and tools to create machines that will perform some tasks.
Outstanding inventors:
- Johannes Gutenberg: he invented the modern printing press with movable metal-type in 1450.
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| Modern printing press |
- John Napier: he published the first table of logarithms to simplify and speed up the calculations.
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| 1st table of logarithms |
- William Oughtred: invented the slide rule with two sliding scales that are graduated according to the logarithms of the amounts that were calculated.
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| Slide rule with two sliding scales |
- Wilhelm Schickard: he built the first automatic calculator in 1623.
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| 1st automatic calculator |
- Blaise Pascal: famous because of his contributions to probability theory, research on fluids and clarification of concepts such as pressure and vacuum.
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| Blaise Pascal |
- Gottfired Leibniz: invented calculus and binary system. He also invented the Stepped Reckoner that could multiply 5 digit and 12 digit numbers.
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| Stepped Reckoner |
- Joseph-Marie Jacquard: inventor of the Jacquard loom, that is the basis of the modern automatic loom used in the textile industry.
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| Jacquard Loom |
- Charles Xavier: built the first mechanical calculator.
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| 1st mechanical calculator |
- Charles Babbage: invented the speedometer and the locomotive cowcatcher.
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| Charles Babbage |
- Lady Ada Augusta Lovelace Byron: she was the first computer programmer.
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| Lady Ada Augusta Lovelace Byron |
ELECTRO-MECHANICAL AGE
The discovery of the ways to harness electricity was the key advance made during this period.
The beginnings of telecommunication:
Invented by Alessandro Volta, it is considered to be the first source of stored electricity in the 8th century.
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| Voltaic Battery |
Samuel Morse invented the first magnetic telegraph in 1832.
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| Telegraph |
The first succesful bi-directional transmission of clear speech by Bell and Watson was made on 1876 when Bell spoke into his device.
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| Bell and Watson |
Electromechanical computing:
In 1853, Pehr and Scheutz completed their tabulating machine capable of processing fifteen-digit numbers, printing out results and rounding off the eight digit.
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| Tabulating machine |
Type of electro-mechanical adding machine. The orginical design was patented in 1887 by Dorr Felt.
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| Comptometer |
In 1889, Felt's comptograph, containing built-in printer, is introduced.
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| Comptograph |
It is a piece of stiff paper that contains digital information represented by holes in predefined positions. It was used through the 20th century in unit record for input, processing and data storage.
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| Punched card |
The first efficient four-function calculator invented by Otto Shweiger
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| Millionaire |
It was developed by Lee de Forest in 1906, it provides electricity controlled by switch.
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| Lee de Forest and his Vacuum Tube |
ELECTRONIC AGE
The age is what we currently live in. It can be defined as the time between 1940 and right now.
The ENIAC was the first high-speed, digital computer capable of being reprogrammed to solve a full range of computing problems. This first computer was designed to be used by the US Army for artillery firing tables.
Four generations of computers
1st Generation (1951 - 1958)
- Vacuum tubes as theas their main logic elements.
- Punch cards to input and externallly store data.
- Rotating magnetic drums for internal storage of data and programs.
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| 1st generation computer |
2nd Generation (1959 - 1963)
- Vacuum tubes replaced ny trasistors as main logic element .
- AT&T's Bell Laboratories in the 1940's
- Crystalline mineral materials called semiconductors could be used in the design of a device called a transistor.
- Magnetic tape ans disks began to replae punched cards as external storage devices.
- High level programming languages
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| 2nd generation computer |
3rd Generation (1964 - 1978)
- Individual transistors wee replaced by integrated circuits.
- Magnetic core internal memories began to give way to a new form, metal oxide semiconductor (MOS) memory, which, like integrated circuits, used silicon-backed chips.
- Operating systemas
- Advanced programming languages like BASIC developed.
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| 3rd generation computer |
4th Generation (1979 - present)
- Microprocessors that contained memory, logic and control circuits (an entire CPU) on a single chip.
-Which allowed for home-use personal computers or PC's.
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4th generation computers
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