History of computing
The earliest reference of the term computer comes from the French word of the same in 1631, derived from the Latin word computare meaning "to count, to sum up". The word is formed from the two roots: com- meaning "with", and +putare meaning "to reckon"(originally "to prune")[1].
Early Methods of Counting (300 - 1400 A.D.)
Before the arrival of mechanical or analogue computing, ancient civilizations required methods to quantify properties of their livelihoods. Circa 300 B.C., the Slamis Tablet[2], discovered on the island of Salamis in 1846, was used by the Babylonians to track numbers in their society. On this board, physical markers(indicators) were placed on the various rows or columns that represented different values. The indicators were not physically attached to the board.
Development of counting techniques lead to devices like the Roman hand abacus, which is estimated to have been created some time between 300 B.C. and 500 A.D. A notworthy advancement of the hand abacus was the implementation of permanently attached markers, which are adjusted in position to indicate value. This modification might have contributed to the evolution of the suan-pan, or Chinese abacus, in or around 1200 A.D., that closely resembles the abacus of today.
In the typical modern-day abacus, slidable markers are placed on columns of shafts(typically made from wood or metal) representing powers of ten (.0001, .001, .01, .1, 1, 10, 100 etc), with the top row representing values of "fives" and the bottom representing values of "ones". These markers are permanently attached to the device.
It should be noted that usage of an abacus relies on a concept of "states"; that is whether or not beads are in the "inclusive" or "not-inclusive" positions. To count items on an abacus, a number of beads are shifted over to the represented position that indicates a counted value, and any that are not moved are not counted.
Advanced Techniques (1600 - A.D.)
References
- ↑ "compute", Online Etymology Dictionary. Retrieved on 2007-04-24.
- ↑ The Abacus:A Brief History. Retrieved on 2007-04-24.