General

Data Sizes SI vs IEC

To define data sizes there are two existing systems. On one hand there is the SI Metric system based on the decimal numbers \(10^n\). On the other hand there is the IEC system based on the binary numbers \(2^n\)

\(10^n\)	Decimal	Prefix	Symbol
\(10^{24}\)	1 000 000 000 000 000 000 000 000	yotta	Y
\(10^{21}\)	1 000 000 000 000 000 000 000	zetta	Z
\(10^{18}\)	1 000 000 000 000 000 000	exa	E
\(10^{15}\)	1 000 000 000 000 000	peta	P
\(10^{12}\)	1 000 000 000 000	tera	T
\(10^{9}\)	1 000 000 000	giga	G
\(10^{6}\)	1 000 000	mega	M
\(10^{3}\)	1 000	kilo	k
\(10^{2}\)	100	hecto	h
\(10^{1}\)	10	deca	da
\(10^{0}\)	1
\(10^{-1}\)	0.1	deci	d
\(10^{-2}\)	0.01	centi	c
\(10^{-3}\)	0.001	mili	m
\(10^{-6}\)	0.000 001	micro	\(\mu\)
\(10^{-9}\)	0.000 000 001	nano	n
\(10^{-12}\)	0.000 000 000 001	pico	p
\(10^{-15}\)	0.000 000 000 000 001	femto	f
\(10^{-18}\)	0.000 000 000 000 000 001	atto	a
\(10^{-21}\)	0.000 000 000 000 000 000 001	zepto	z
\(10^{-24}\)	0.000 000 000 000 000 000 000 001	yocto	y

The problem with the SI system for defining datasizes is that the data size base unit is \(2^n\)

Datasizes

1 bytes = 8 bit

IEC

\(2^n\)	Value	IEC Prefix	IEC Symbol
\(2^{10}\)	1024	kibibyte	KiB
\(2^{20}\)	1048576	mebibytes	MiB
\(2^{30}\)	1073741824	gibibyte	GiB
\(2^{40}\)	1099511627776	tebibyte	TiB
\(2^{50}\)	1125899906842624	pebibyte	PiB
\(2^{60}\)	1152921504606846976	exbibyte	EiB
\(2^{70}\)	1180591620717411303424	zebibyte	ZiB
\(2^{80}\)	1208925819614629174706176	yobibyte	YiB

SI

\(10^n\)	Value	SI Prefix	SI Symbol
\(10^3\)	1 000	kilobyte	kB
\(10^6\)	1 000 000	megabyte	MB
\(10^9\)	1 000 000 000	gigabyte	GB
\(10^{12}\)	1 000 000 000 000	terabyte	TB
\(10^{15}\)	1 000 000 000 000 000	petabyte	PB
\(10^{18}\)	1 000 000 000 000 000 000	exabyte	EB
\(10^{21}\)	1 000 000 000 000 000 000 000	zettabyte	ZB
\(10^{24}\)	1 000 000 000 000 000 000 000 000	yottabyte	YB