. | Bytes | Bits | . | Deviation from 10^x | 1 bit = 1 byte = 1 kilobyte = 1 megabyte = 1 gigabyte = 1 terabyte = 1 petabyte = 1 exabyte = 1 zettabyte = 1 yottabyte = 1 xonabyte = 1 wekabyte = 1 vundabyte = |
.125 byte. = 1 byte. = 1,024 bytes = 1,048,576 bytes = 1,073,741,824 bytes = 1,099,511,627,776 bytes = 1,125,899,906,842,624 bytes = 1,152,921,504,606,846,976 bytes = 1,180,591,620,717,411,303,424 bytes = 1,208,925,819,614,629,174,706,176 bytes = 1,237,940,039,285,380,274,899,124,224 bytes = 1,267,650,600,228,229,401,496,703,205,376 bytes = 1,298,074,214,633,706,907,132,624,082,305,024 bytes = |
1 bit. 8 bits 8,192 bits 8,388,608 bits 8,589,934,592 bits 8,796,093,022,208 bits 9,007,199,254,740,992 bits 9,223,372,036,854,775,808 bits 9,444,732,965,739,290,427,392 bits 9,671,406,556,917,033,397,649,408 bits 9,903,520,314,283,042,199,192,993,792 bits 10,141,204,801,825,835,211,973,625,643,008 bits 10,384,593,717,069,655,257,060,992,658,440,192 bits |
. x 3 6 9 12 15 18 21 24 27 30 33 |
. . 24 48,576 73,741,824 99,511,627,776 125,899,906,842,624 152,921,504,606,846,976 180,591,620,717,411,303,424 208,925,819,614,629,174,706,176 237,940,039,285,380,274,899,124,224 267,650,600,228,229,401,496,703,205,376 298,074,214,633,706,907,132,624,082,305,024 |
. | Bytes | 2^X | Bits | 1 bit = 1 byte = 1 kilobyte = 1 megabyte = 1 gigabyte = 1 terabyte = 1 petabyte = 1 exabyte = 1 zettabyte = 1 yottabyte = 1 xonabyte = 1 wekabyte = 1 vundabyte = |
.125 byte. = 1 byte. = 1024 bytes = 1048576 bytes = 1073741,824 bytes = 1099511627776 bytes = 1125899906842624 bytes = 1152921504606846976 bytes = 1180591620717411303424 bytes = 1208925819614629174706176 bytes = 1237940039285380274899124224 bytes = 1267650600228229401496703205376 bytes = 1298074214633706907132624082305024 bytes = |
2^10 2^20 2^30 2^40 2^50 2^60 2^70 2^80 |
1 bit. 8 bits 8192 bits 8388608 bits 8589934592 bits 8796093022208 bits 9007199254740992 bits 9223372036854775808 bits 9444732965739290427392 bits 9671406556917033397649408 bits 9903520314283042199192993792 bits 10141204801825835211973625643008 bits 10384593717069655257060992658440192 bits |
Some interesting facts about what these various-sized bytes can store:
* 1 bit: a binary decision |
The creation of these newest terms is interesting. The older prefixes, kilo-,
mega-, giga-, and tera-, are generally understood to be derived from the ancient
Greek words for "thousand," "large," "giant," and "monster," respectively. But
peta- departs from the traditional pattern to the extent that there is no Greek
(or any other) word to explain it in its present form.
Considering the context, however, (preceding exa-) it is the Greek prefix for
"five," penta-, minus the letter "n." The reduction of five letters to four
makes it similar in this respect to the existing prefixes. On the other hand,
exa- has been reduced to three letters by dropping the "h" from hexa-, the Greek
prefix for "six," possibly because the "h" would be silent in standard French.
According to a CGPM report, prefixes meaning "five" and "six" are used because
10**15 and 10**18 are fifth and sixth in the ascending series 10**3, 10**6,
10**9, and 10**12.
(If tera- for 10**12 were taken to mean the Greek prefix for "four," te(t)ra-,
minus the second letter "t," that would be an additional reason for its being
followed by pe(n)ta- as the prefix for "five." However, the acceptance of tera-
as derived from "teras," the Greek word for "monster," seems to be universal.)
The use of Greek words for magnitudes through 10**12 turns out to be awkward in
the late twentieth century, since it is difficult to extend the series easily.
(After all, what could be bigger than giants and monsters?) Yet it would be even
more awkward to throw away the established size-words and start from scratch.
Therefore, a backward switch in midstream from a Greek-conceptual to the
original Greek-numerical basis (using kilo- for "thousand") is announced as the
"expedient" thing to do, simultaneously preserving tradition and leaving the way
open to further expansion.
Since 1975, though, and so quietly that current editions of the Encyclopedia
Brittanica and World Almanac do not recognize their advent, prefixes with
corresponding symbols have materialized for 10**21 and 10**24: zetta- (Z) and
yotta- (Y), denoting sextillions and septillions. With these it is easy to see
yet another change of direction. While still disyllabic, the names are now
semi-artificial (echoing Greek zeta and iota) and symbol-driven, and the series
is now based on the Latin alphabet, starting with the last letter and moving
backwards, with a long way to go before reaching A. Could this be the last
terminological contortion?
Etymology of Units
by PC Hariharan
1.Kilo Greek khilioi = 1000
2.Mega Greek megas = great, e.g., Alexandros Megos
3.Giga Latin gigas = giant
4.Tera Greek teras = monster
5.Peta Greek pente = five, fifth prefix, peNta - N = peta
6.Exa Greek hex = six, sixth prefix, Hexa - H = exa Remember, in standard French,
the initial H is silent, so they
would pronounce Hexa as Exa.
It is far easier to call it Exa for everyone's sake, right?
7.Zetta almost homonymic with Greek Zeta, but last letter of the Latin alphabet
8.Yotta almost homonymic with Greek iota, but penultimate letter of the Latin alphabet.
The first prefix is number-derived; second, third, and fourth are based on mythology. Fifth and sixth are supposed to be
just that: fifth and sixth. But, with the seventh, another fork has been taken. The General Conference of Weights and
Measures (CGMP, from the French; they have been headquartered, since 1874, in Sevres on the outskirts of Paris) has
now decided to name the prefixes, starting with the seventh, with the letters of the Latin alphabet, but starting from the end.
Now, that makes it all clear! Remember, both according to CGMP and SI, the prefixes refer to powers of 10. Mega is
10**6, exactly 1,000,000, kilo is exactly 1000, not 1024.
The prefix is placed on the front of words to imply a multiple of millions or
billions,
or to show a division by (negative powers of ten) a number, as in
microsecond.
These prefixes are used with metric measurements. They are also called SI prefixes,
because the metric units are known as the SI Units, where SI means Systeme Internationale.
Powers of 10 - SI Prefixes
prefix letter power of
10 multiplier US English words Greater than one - a multiple
kilo K 3 1,000 one
thousand mega M 6 1,000,000 one
million giga G 9 1,000,000,000 one
billion tera T 12 1,000,000,000,000 one
trillion peta P 15 1,000,000,000,000,000
one quadrillion exa E 18 1,000,000,000,000,000,000
one
quintillion zetta
Z 21 1,000,000,000,000,000,000,000 one
sextillion yotta
Y 24 1,000,000,000,000,000,000,000,000 one
septillion Less than one - a fraction
milli m -3 1/1,000 one
thousandth micro µ
* -6 1/1,000,000 one
millionth nano n -9 1/1,000,000,000 one
billionth pico p -12 1/1,000,000,000,000
one trillionth femto f -15 1/1,000,000,000,000,000
one
quadrillionth atto a -18 1/1,000,000,000,000,000,000
one quintillionth zecto
z -21 1/1,000,000,000,000,000,000,000
one sextillionth yocto
y -24 1/1,000,000,000,000,000,000,000,000
one septillionth * note: the letter for micro is the Greek letter 'mu'.
Examples:
One picosecond is 0.0000000000001 second, or 10-12 second.
(Some say "pie-co", some say "pee-co.")
A terawatt is 1,000,000,000,000 watts of energy.
166 Megahertz means 166 million cycles per second.
Jim Binder
Since shortly after the French Revolution of 1789, scientists--and eventually
computer scientists--have found it convenient to refer to large quantities of
various units of measure with verbal prefixes and letter symbols. Thus kilo-
(symbol K) and mega- (M) stand for 10**3 and 10**6, thousands and millions.
After World War II, this pair of terms was extended, three zeroes at a time, to
giga- (G) and tera- (T), standing for 10**9 and 10**12, billions and trillions
(usage here and below is American). In 1975, the world arbiter of the metric
system, the General Conference of Weights and Measures (CGPM), based at Sevres
near Paris, agreed to add two more terms to the ascending series: peta- (P) and
exa- (E) for 10**15 and 10**18, quadrillions and quintillions.