Byte
A byte is a unit of measurement of the size of information on a computer or other electronic device. A single byte is usually eight bits. Some early computers used six bits for each byte. Bits are the smallest unit of storage on a computer, a single on/off value. Bytes are often represented by the capital letter B, bits by a lower case b.
A single typed character (for example, 'x' or '8') is stored in one byte. The character is held as a binary number which encodes a text character. To map each number to a character an agreed code such as EBCDIC or ASCII is needed. EBCDIC is a character encoding used mainly on mainframe computers. It uses 8 bits per byte. ASCII is another encoding that only uses seven bits. Extended ASCII uses 8 bits to give more types of characters, mostly used on personal computers.
The byte is the smallest useful unit of measure to show how many characters a computer (or electronics device) can hold. This is useful for things like RAM, or storage devices like USB drives and other types of Flash memory. Sending of data (for a modem or wi-fi) is usually measured in bits, not bytes.
On modern computers one byte is equal to eight bits. Some early computers used fewer bits for each byte. To tell them apart, computer scientists called an 8 bit byte an octet. In modern usage, an octet and a byte are the same.
Abbreviation
[change | change source]The symbol for "byte" is "B". Sometimes a lowercase "b" is used, but this use is incorrect because "b" is actually the IEEE symbol for "bit". The IEC symbol for bit is bit. For example, "MB" means "megabyte" and "Mbit" means "megabit". The difference is important because 1 megabyte (MB) is 1,000,000 bytes, and 1 megabit (Mbit) is 1,000,000 bits or 125,000 bytes. It's easy to confuse the two, but bits are much smaller than bytes, so the symbol "b" should be used when referring to "bits" and an uppercase "B" when referring to "bytes".
Names for larger units
[change | change source]For large data, byte is often used with a binary prefix:
- Kilobyte (kB) (103)/kibibyte (KB) (210)
- Megabyte (MB) (106)/mebibyte (MiB) (220)
- Gigabyte (GB) (109)/gibibyte (GiB) (230)
- Terabyte (TB) (1012)/tebibyte (TiB) (240)
The following terms represent even larger units of bytes, but are very rarely used:
- Petabyte (PB) (1015)/pebibyte (PiB) (250)
- Exabyte (EB) (1018)/exbibyte (EiB) (260)
- Zettabyte (ZB) (1021)/Zebibyte (ZiB) (270)
- Yottabyte (YB) (1024)/Yobibyte (YiB) (280)
- Ronnabyte (RB) (1027)/Robibyte (RiB) (290)
- Quettabyte (QB) (1030)/Quebibyte (QiB) (2100)
The following terms represent even larger unofficial units of bytes. (They are likely to never be used in future computing):
- Saganbyte (SB) (2110)
- Pijabyte (PjB) (2120)
- Alphabyte (AB) (2130)
- Pectrolbyte (PcB) (2140)
- Bolgerbyte (BoB) (2150)
- Sambobyte (SaB) (2160)
- Quesabyte (QB) (2170)
- Kinsabyte (KiB) (2180)
- Rutherbyte (RB) (2190)
- Dubnibyte (DB) (2200)
- Hassiubyte (HaB) (2210)
- Meitnerbyte (MnB) (2220)
- Darmstadbyte (DrB) (2230)
- Roentbyte (RaB) (2240)
- Sophobyte (SoB) (2250)
- Coperbyte (CoB) (2260)
- Koentekbyte (KoB) (2270)
- Glossybyte (GsB) (2280)
- Snugbyte (SuB) (2290)
- Grandbyte (GrB) (2299)
- Doombyte (DmB) (2309)
- Godbyte (GdB) (2319)
- Superbyte (SpB) (2329)
- Googolbyte (GgB) (2339)
Byte Chart
[change | change source]According to the International Electrotechnical Commission (IEC), who sets many computer standards, these charts show how bytes should be referred to.
People who refer to 1 kilobyte as 1,024 bytes, for example, are technically incorrect; 1,024 bytes should be referred to as 1 kibibyte, according to the IEC. [1] However, using 1024 for kilo and 1048576 for mega, etc. was widely practiced before the IEC standards were set in 1998. There is some confusion and mixing of terms in the marketplace. Computer memory is still referred to in powers of 2, so 1KB of memory is 1024 bytes, whereas in computer data storage powers of 10 are used, so 1KB is 1000 bytes.
"kilo-" = 1,000
[change | change source]When using standard metric names like "kilo-", "mega-" and "giga-", they should follow the same measure that other metric measurements use, like kilometer (1 kilometer = 1,000 meters), or gigahertz (1 gigahertz = 1,000,000,000 hertz) for example.
| Unit | Number | Short scale | Long scale | Scientific,E Notation/ Power of 10 |
|---|---|---|---|---|
| Byte
(B) |
1 | 1
byte |
1
byte |
1*100,1E0 / 100 |
| Kilobyte
(KB) |
1,000 | 1
thousand bytes |
1
thousand bytes |
1*103,1E3 / 103 |
| Megabyte (MB) | 1,000,000 | 1
million bytes |
1
million bytes |
1*106,1E6 / 106 |
| Gigabyte (GB) | 1,000,000,000 | 1
billion bytes |
1
billion bytes |
1*109,1E9 / 109 |
| Terabyte
(TB) |
1,000,000,000,000 | 1
trillion bytes |
1
trillion bytes |
1*1012,1E12 / 1012 |
| Petabyte
(PB) |
1,000,000,000,000,000 | 1
quadrillion bytes |
1
quadrillion bytes |
1*1015,1E15 / 1015 |
| Exabyte
(EB) |
1,000,000,000,000,000,000 | 1
quintillion bytes |
1
quintillion bytes |
1*1018,1E18 / 1018 |
| Zettabyte (ZB) | 1,000,000,000,000,000,000,000 | 1
sextillion bytes |
1
sextillion bytes |
1*1021,1E21 / 1021 |
| Yottabyte (YB) | 1,000,000,000,000,000,000,000,000 | 1
septillion bytes |
1
septillion bytes |
1*1024,1E24 / 1024 |
| Brontobyte (BB) (unofficial) | 1,000,000,000,000,000,000,000,000,000 | 1
octillion bytes |
1
octillion bytes |
1*1027,1E27 / 1027 |
| Geopbyte (GpB/GeB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000 | 1
nonillion bytes |
1
nonillion bytes |
1*1030,1E30 / 1030 |
| Saganbyte (SB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000 | 1
Decillion bytes |
1
Decillion bytes |
1*1033,1E33 / 1033 |
| Pijabyte
(PjB) (unofficial) |
1,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Undecillion bytes |
1
Undecillion bytes |
1*1036,1E36 / 1036 |
| Alphabyte (AB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Duodecillion bytes |
1
Duodecillion bytes |
1*1039,1E39 / 1039 |
| Pectrolbyte (PcB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Tredecillion bytes |
1
Tredecillion bytes |
1*1042,1E42 / 1042 |
| Bolgerbyte (BoB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Quattuordecillion bytes |
1
Quattuordecillion bytes |
1*1045,1E45 / 1045 |
| Sambobyte (SaB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Quindecillion bytes |
1
Quindecillion bytes |
1*1048,1E48 / 1048 |
| Quesabyte (QB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Sexdecillion bytes |
1
Sexdecillion bytes |
1*1051,1E51 / 1051 |
| Kinsabyte (KiB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Septendecillion bytes |
1
Septendecillion bytes |
1*1054,1E54 / 1054 |
| Rutherbyte (RB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Octodecillion bytes |
1
Octodecillion bytes |
1*1057,1E57 / 1057 |
| Dubnibyte (DB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Novemdecillion bytes |
1
Novemdecillion bytes |
1*1060,1E60 / 1060 |
| Hassiubyte (HaB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Vigintillion bytes |
1
Vigintillion bytes |
1*1063,1E63 / 1063 |
| Meitnerbyte (MnB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Unvigintillion bytes |
1
Unvigintillion bytes |
1*1066,1E66 / 1066 |
| Darmstadbyte (DrB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Duovigintillion bytes |
1
Duovigintillion bytes |
1*1069,1E3 / 1069 |
| Roentbyte (RaB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Trevigintillion bytes |
1
Trevigintillion bytes |
1*1072,1E3 / 1072 |
| Sophobyte (SoB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Quattuorvigintillion bytes |
1
Quattuorvigintillion bytes |
1*1075,1E3 / 1075 |
| Coperbyte (CoB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Quinvigintillion bytes |
1
Quinvigintillion bytes |
1*1078,1E78 / 1078 |
| Koentekbyte (KoB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Sexvigintillion bytes |
1
Sexvigintillion bytes |
1*1081,1E81 / 1081 |
| Glossybyte (GsB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Septenvigintillion bytes |
1
Septenvigintillion bytes |
1*1084,1E84 / 1084 |
| Snugbyte (SuB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Octovigintillion bytes |
1
Octovigintillion bytes |
1*1087,1E87 / 1087 |
| Grandbyte (GrB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Nonvigintillion bytes |
1
Nonvigintillion bytes |
1*1090,1E90 / 1090 |
| Doombyte (DmB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Trigintillion bytes |
1
Trigintillion bytes |
1*1093,1E93 / 1093 |
| Godbyte (GdB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Untrigintillion bytes |
1
Untrigintillion bytes |
1*1096,1E96 / 1096 |
| Superbyte (SpB) (unofficial) | 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Duotrigintillion bytes |
1
Duotrigintillion bytes |
1*1099,1E99 / 1099 |
| Googolbyte (GgB) (unofficial) | 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 | 1
Googol bytes |
1
Googol bytes |
1*10100,1E100 / 10100 |
"kibi-" = 1,024
[change | change source]Since computers are very complex digital devices that are based on the binary numeral system rather than the commonly-used decimal numeral system or binary coded decimal system, there are many situations where the standard metric system does not work well, particularly with memory sizes for a computer or storage device. If a memory or storage device uses a binary number for addresses, the number of different positions to be accessed (the size of the memory) can be expressed as a power of 2, rather than a power of 10.
| Unit | Number | Maths |
|---|---|---|
| Byte
(B) |
1 | 20 bytes |
| Kibibyte
(KiB) |
1,024 | 210 bytes |
| Mebibyte
(MiB) |
1,048,576 | 220 bytes |
| Gibibyte
(GiB) |
1,073,741,824 | 230 bytes |
| Tebibyte
(TiB) |
1,099,511,627,776 | 240 bytes |
| Pebibyte
(PiB) |
1,125,899,906,842,624 | 250 bytes |
| Exbibyte
(EiB) |
1,152,921,504,606,846,976 | 260 bytes |
| Zebibyte
(ZiB) |
1,180,591,620,717,411,303,424 | 270 bytes |
| Yobibyte
(YiB) |
1,208,925,819,614,629,174,706,176 | 280 bytes |
| Bronbibyte
(BiB) (unofficial) |
1,237,940,039,285,380,274,899,124,224 | 290 bytes |
| Gebibyte
(GeiB) (unofficial) |
1,267,650,600,228,229,401,496,703,205,376 | 2100 bytes |
| Sagbibyte
(SiB) (unofficial) |
1,298,074,214,633,706,907,132,624,082,305,024 | 2110 bytes |
| Pijbibyte
(PjiB) (unofficial) |
1,329,227,995,784,915,872,903,807,060,280,344,576 | 2120 bytes |
| Alphbibyte
(AiB) (unofficial) |
1,361,129,467,683,753,853,853,498,429,727,072,845,824 | 2130 bytes |
| Pectbibyte
(PciB) (unofficial) |
1,393,796,574,908,163,946,345,982,392,040,522,594,123,776 | 2140 bytes |
| Bolgbibyte (BoiB) (unofficial) | 1,427,247,692,705,959,881,058,285,969,449,495,136,382,746,624 | 2150 bytes |
| Sambibyte (SaiB) (unofficial) | 1,461,501,637,330,902,918,203,684,832,716,283,019,655,932,542,976 | 2160 bytes |
| Quesbibyte (QiB)
(unofficial) |
1,496,577,676,626,844,588,240,573,268,701,473,812,127,674,924,007,424 | 2170 bytes |
| Kinsbibyte
(KiiB) (unofficial) |
1,532,495,540,865,888,858,358,347,027,150,309,183,618,739,122,183,602,176 | 2180 bytes |
| Ruthbibyte
(RiB) (unofficial) |
1,569,275,433,846,670,190,958,947,355,801,916,604,025,588,861,116,008,628,224 | 2190 bytes |
| Dubbibyte
(DiB) (unofficial) |
1,606,938,044,258,990,275,541,962,092,341,162,602,522,202,993,782,792,835,301,376 | 2200 bytes |
| Hassbibyte (HaiB) (unofficial) | 1,645,504,557,321,206,042,154,969,182,557,350,504,982,735,865,633,579,863,348,609,024 | 2210 bytes |
| Meitbibyte (MniB) (unofficial) | 1,684,996,666,696,914,987,166,688,442,938,726,917,102,321,526,408,785,780,068,975,640,576 | 2220 bytes |
| Darmbibyte (DriB)
(unofficial) |
1,725,436,586,697,640,946,858,688,965,569,256,363,112,777,243,042,596,638,790,631,055,949,824 | 2230 bytes |
| Roentbibyte (RaiB) (unofficial) | 1,766,847,064,778,384,329,583,297,500,742,918,515,827,483,896,875,618,958,121,606,201,292,619,776 | 2240 bytes |
| Sophbibyte (SoiB) (unofficial) | 1,809,251,394,333,065,553,493,296,640,760,748,560,207,343,510,400,633,813,116,524,750,123,642,650,624 | 2250 bytes |
| Copbibyte
(CoiB) (unofficial) |
1,852,673,427,797,059,126,777,135,760,139,006,525,652,319,754,650,249,024,631,321,344,126,610,074,238,976 | 2260 bytes |
| Koentbibyte (KoiB) (unofficial) | 1,897,137,590,064,188,545,819,787,018,382,342,682,267,975,428,761,855,001,222,473,056,385,648,716,020,711,424 | 2270 bytes |
| Glossbibyte (GsiB) (unofficial) | 1,942,668,892,225,729,070,919,461,906,823,518,906,642,406,839,052,139,521,251,812,409,738,904,285,205,208,498,176 | 2280 bytes |
| Snugbibyte (SuiB) (unofficial) | 1,989,292,945,639,146,568,621,528,992,587,283,360,401,824,603,189,390,869,761,855,907,572,637,988,050,133,502,132,224 | 2290 bytes |
| Grandbibyte (GriB)
(unofficial) |
1,018,517,988,167,243,043,134,222,844,204,689,080,525,734,196,832,968,125,318,070,224,677,190,649,881,668,353,091,698,688 | 2299 bytes |
| Doombyte (DmiB) (unofficial) | 1,042,962,419,883,256,876,169,444,192,465,601,618,458,351,817,556,959,360,325,703,910,069,443,225,478,828,393,565,899,456,512 | 2309 bytes |
| Godbibyte (GdiB) (unofficial) | 1,067,993,517,960,455,041,197,510,853,084,776,057,301,352,261,178,326,384,973,520,803,911,109,862,890,320,275,011,481,043,468,288 | 2319 bytes |
| Supbibyte
(SpiB) (unofficial) |
1,093,625,362,391,505,962,186,251,113,558,810,682,676,584,715,446,606,218,212,885,303,204,976,499,599,687,961,611,756,588,511,526,912 | 2329 bytes |
| Googolbibyte (GgiB) (unofficial) | 1,119,872,371,088,902,105,278,721,140,284,222,139,060,822,748,617,324,767,449,994,550,481,895,935,590,080,472,690,438,746,635,803,557,888 | 2339 bytes |
References
[change | change source]- ↑ "official SI units for computers". NIST. Retrieved 4 April 2013.