The first numbers

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The first numbers
Ishango Bones, Africa
20,000 years ago
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Egyptian numbers
5,000 years ago
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Babylonian numbers
4,000 years ago
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Chinese numbers
Today
3,000 years ago using bamboo rods
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Indian numbers
2,500 years ago
What we the Arabs use for numerals is a
selection of the best and most regular figures in
India. Al-Biruni 1000AD
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Arab numbers
When I consider what people generally want in
calculating, I found that it always is a number.
I also observed that every number is composed of
units, and that any number may be divided into
units. Moreover, I found that every number which
may be expressed from one to ten, surpasses the
preceding by one unit afterwards the ten is
doubled or tripled just as before the units were
thus arise twenty, thirty, etc. until a hundred
then the hundred is doubled and tripled in the
same manner as the units and the tens, up to a
thousand ... so forth to the utmost limit of
numeration.
Abu Ja'far Muhammad ibn Musa al-Khwarizmi,
Baghdad 800
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Greek numbers
2,000 years ago
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Mayan numbers
1,000 years ago
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Inca numbers
Quipu, 1500
Garcilaso de la Vega, whose mother was an Inca
and whose father was Spanish, wrote According
to their position, the knots signified units,
tens, hundreds, thousands, ten thousands and,
exceptionally, hundred thousands, and they are
all well aligned on their different cords as the
figures that an accountant sets down, column by
column, in his ledger.
Yupana, Inca counting board
To see them use another kind of calculator, with
maize kernels, is a perfect joy. In order to
carry out a very difficult computation for which
an able computer would require pen and paper,
these Indians make use of their kernels. They
place one here, three somewhere else and eight, I
know not where. They move one kernel here and
there and the fact is that they are able to
complete their computation without making the
smallest mistake. as a matter of fact, they are
better at practical arithmetic than we are with
pen and ink.
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Today
Computer numbers Binary numbers
01 10 11 100 101 110 1000 1001 1010 1100
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