Science

Mathematics

General
Numbers
Timeline

The natural numbers or whole numbers are the ones we use in counting. We learn them at an early age, perhaps pairing them with our fingers or else learning to chant thier names in order 'one, two, three, four, ...'. Important features of our number systems, these numbers can be used to count sets of objects, and for a naturally ordered progression that has a first number, the number 1, but no last number; so no matter how big a number you come up with, I can always reply with a bigger one -- simply by adding 1.

However, even quite simple arithmetic, as we shall see, cannot be carried out wholly within the natural numbers. Ordinarily we take the principles that govern each such systems for granted, yet merely to be able to subtract and divide, for example, requires other, more complex number systems, such as fractions and negative numbers.

Historical Systems:

Egyptian: earliest example of a number system. Hyeroglyphs  were used to represent 1, 10, 100, 1000, 10000, 100000, and 1000000. Numbers wer formed by grouping multile occurences of the symbols from right to left.
Babylonian: based on the number 60 (sexagesimal)
Greek
Roman
Chinese

Base Systems:

Decimal (base 10) is our most common number system today.
Binary (base 2) uses only the numbers 0 and 1.  Commonly used in the representation of  numbers in computers since those two numbers represent the two states of a switch (off and , respectively)
Octal (base 8) mostly in computers
Hexadecimal (base 16) mostly used in computers

Names for numbers

Tithe	1/10		Soloist	1
Pair, couple, brace	2		Duet	2
Half dozen	6		Trio	3
Dozen	12		Quartet	4
Baker's dozen	13		Quintet	5
Score	20		Sextet	6
Half century	50		Septet	7
Century	100		Octet	8
Gross	144

Prefixes

Semi, hemi, demi	1/2		Oct, octa, octo	8
Uni	1		Non, nona, ennea	9
Bi, di	2		Dec, deca	10
Tri, ter	3		Hendca, undec, undeca	11
Tetra, tetr, tessera, quadri, quadr	4		Dodeca	12
Pent, penta, quinqu, quinque, quint	5		Trideca	13
Sex, sexi, hex, hexa	6		Quindeca	15
Hept, hepta, sept, septi, septam	7		Icos, icosa, icosi	20

Powers of 10 (in decending order of value)

Tera	T			Centi	c
Giga	G			Milli	m
Mega	M			Micro	µ
Kilo	k			Nano	n
Hect, hecto	h			Pico	p
Dec, deca	D			Femto	f
deci	d			Atto	a