Computers Used in the Ages Past
A computer is defined as a device that is given information, known as input, and is then programmed to use that information to return a result, known as output. For example, typing on a keyboard is the input, while the characters shown on a screen is the output.
The Abacus - Around 3000 BC
![Picture](/uploads/1/7/8/0/17806183/1363325705.jpg)
Chinese Suanpan Abacus donated to National Air and
Space Museum by Mr. Richard Lynch.
http://airandspace.si.edu/images/collections/media/full/A19970126000.JPG
Abacus is a Latin word that has its origins in the Greek words abax or abakon (meaning "table" or "tablet") which in turn, possibly originated from the Semitic word abq, meaning "sand" 1 (Ifrah).
The abacus is widely regarded as one of the first computers to come about. Early versions of the abacus could be found in China around 5,000 years ago as a simple board with wires and beads, although it is not until around 300 BC that it became an efficient mathematical device. Also around that time frame, the abacus had a more wide spread usage in European countries, such as Romans, Chinese, Japanese, Koreans, Russians, and more throughout the centuries.
The usage of the abacus is for mathematical operations varying from simple addition, to even finding the square root of a number. The abacus above is called a Suanpan, used for counting in both decimal (0-9) and hexadecimal (0-15). Each bead on the top is treated as five while each bottom bead is treated as the simply one. Every column is treated as one digit.
To read the abacus, just count the beads that are closest to the center (the bottom beads that lifted up and the top beads that are dropped down). In the diagram to the left, the ones digit is the number 8 because one top bead is dropped down, while three bottom beads are lifted up (five plus three = eight).
The Antikythera Mechanism - Around 100 BC
![Picture](/uploads/1/7/8/0/17806183/1362194355.png)
The Antikythera mechanism was developed sometime during first century BC by the Greeks, technology that was a millennia ahead of its time. It is an ancient computer known best as the first analog computer in history.
An analog computer uses constantly changing physical variables to give approximate information. A thermometer, for instance, is a simple analog computer. As the temperature changes, the mercury in the thermometer moves accordingly.
The Antikythera mechanism is an analog computer because it uses over 30 gears to give rather accurate positions of the sun, moon and other planets
An analog computer uses constantly changing physical variables to give approximate information. A thermometer, for instance, is a simple analog computer. As the temperature changes, the mercury in the thermometer moves accordingly.
The Antikythera mechanism is an analog computer because it uses over 30 gears to give rather accurate positions of the sun, moon and other planets
Slide Rule - Around 1620
![Picture](/uploads/1/7/8/0/17806183/1362195845.jpg)
During the 1620's, another analog computer was invented by a man named William Oughtred. They are basically two objects marked with a variety of scales that will slide next to each other. Aligning the numbers on different types of scales will result in a variety of calculations, from multiplication or even trigonometry functions.
They depend greatly on the users skills for any type of accuracy, however they soon became highly popular world wide. It became a tool used most commonly among engineers, but it was also seen in the air force or among navigators.
The slide rule remained a popular tool up until around the 1950's, during which electrical calculators began to come into the market. Even so, there are still those who prefer the slide rule as a computing device over the pocket calculators used commonly today.
They depend greatly on the users skills for any type of accuracy, however they soon became highly popular world wide. It became a tool used most commonly among engineers, but it was also seen in the air force or among navigators.
The slide rule remained a popular tool up until around the 1950's, during which electrical calculators began to come into the market. Even so, there are still those who prefer the slide rule as a computing device over the pocket calculators used commonly today.