bit

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A binary digit. In the computer, electronics, and communications fields, “bit” is generally understood as a shortened form of “binary digit.” In a numerical binary system, a bit is either a 0 or 1. Bits are generally used to indicate situations that can take one of two values or one of two states, for example, on and off, true or false, or yes or no. If, by convention, 1 represents a particular state, then 0 represents the other state. For example, if 1 stands for “yes,” then 0 stands for “no.” See also Boolean algebra.

In a computer system a bit is thought of as the basic unit of memory where, by convention, only either a 0 or 1 can be stored. In a computer memory, consecutive bits are grouped to form smaller or larger “units” of memory. Depending upon the design of the computer, units up to 64 bits long have been considered. Although there is common agreement as to the number of bits that make up a byte, for larger memory units the terminology depends entirely on the convention used by the manufacturer. In all of these units the leftmost bit is generally called the most significant bit (msb) and the rightmost the least significant bit (lsb).

Bytes and larger units can be used to represent numerical quantities. In these cases the most significant bit is used to indicate the “sign” of the value being represented. By convention a 0 in the msb represents a positive quantity; a 1 represents a negative quantity. Depending on the convention used to represent these numbers, the remaining bits may then be used to represent the numerical value. In addition to numerical quantities, bytes are used to represent characters inside a computer. These characters include all letters of the English alphabet, the digits 0 through 9, and symbols such as comma, period, right and left parentheses, spaces, and tabs. Characters can be represented using ASCII (American Standard Code for Information Interchange) or EBCDIC (Extended Binary Coded Decimal Interchange Code). The latter is used by some mainframe computers. Computers are set up to handle only one of these two character codes. Generally, the internal representation of a character is different in the two codes. For instance, in ASCII the plus sign is represented by the numerical sequence 00101011, and in EBCDIC, by 01001110.

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[Etymology: binary digit] The single two-valued digit in the binary number system.

informatics From the above, the fundamental measure of memory and transmission capacities, corresponding to a single two-state element, effectively on/off, +/-, etc. Externally in punched cards and paper tape this became hole/no-hole. In information theory it becomes the fundamental measure of information content, with the hartley being the amount required to hold one decimal digit, i.e. = log₂ 10 = 3.321 928~ bits. The typical names for groupings of multiple bits in computers are now as shown in Table 6. See word for a discussion of the variable sizing of this unit.

For bits per second see baud and kibi-.

bit
4	nibble
8	2	byte
16	4	2	half word
32	8	4	2	full word
64	16	8	4	2	double word

bit

The smallest unit of information. One bit corresponds to a “yes or no.” Some examples of a bit of information: whether a light is on or off, whether a switch (like a transistor) is on or off, whether a grain of magnetized iron points up or down.The information in a digital computer is stored in the form of bits.

An earlier term for "binary digit." See bit.

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Advertising: piece of comic or dramatic business such as a gesture, speech, or sound, which often stylistically identifies itself with the performer through repetitive use, such as Johnny Carson's golf swing or Rodney Dangerfield's "I get no respect."

Data processing: binary code used to represent data in a computer memory; acronym for binary digit. Eight bits equal one byte of information. A computer word is 32 bits, or 4 bytes. Information is stored electronically in terms of the presence or absence of an electrical impulse or the polarity of the charge. In a binary system, an impulse is described by a "1" if on (positive) and a "0" if off (negative). Combinations of 1's and 0's, or bits, are used to represent information, depending upon the sequence in which they appear. A bit is, therefore, the smallest unit of information in a computer.

Shorthand term for binary digit. There are only two possible binary digits: 0 and 1. A bit is the smallest unit of memory in a computer.

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noun

1. A tiny amount: crumb, dab, dash, dot, dram, drop, fragment, grain, iota, jot, minim, mite, modicum, molecule, ort, ounce, particle, scrap, scruple, shred, smidgen, speck, tittle, trifle, whit. Chiefly British spot. See big/small/amount.
2. A small portion of food: crumb, morsel, mouthful, piece. Informal bite. See big/small/amount.
3. A usually brief detail of news or information: item, paragraph, piece, squib, story. See words.
4. A rather short period: space, spell, time, while. See big/small/amount.
5. A particular kind of activity: Slang routine. See action/inaction.

bit²

noun

An instrument or means of restraining: brake, bridle, leash, restraint, snaffle. See restraint/unrestraint.

verb

To control, restrict, or arrest: brake, bridle, check, constrain, curb, hold, hold back, hold down, hold in, inhibit, keep, keep back, pull in, rein (back, in. or up), restrain. See restraint/unrestraint.

Idioms beginning with bit:
bite
bite off more than one can chew
bite one's nails
bite one's tongue
bite the dust
bite the hand that feeds you
bitter

In addition to the idiom beginning with bit, also see a bit; champ at the bit; do one's bit; every bit; not a bit; quite a bit; take the bit in one's mouth; two bits.

n

Definition: tiny piece
Antonyms: whole

1. A small tool which fits in the chuck of a brace or drill, and by which it is rotated—thereby cutting or boring a hole.
2. The projecting blade of a key which is cut in a manner to actuate the tumblers and permit the lock bolts to be operated.
3. That part of a soldering iron which transfers heat and solder to the joint. 4. The cutting edge of a plane.

bit, 1

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The binary digit, or 'bit' as it is termed, is the primary unit for measuring information and uncertainty. The bit is a yes/no decision, which may be represented in an information system, or computer, by the two positions of a simple on–off switch. Digital systems are based on 'bits', and their speed may be specified as their maximum 'bit rate'.

The 'Dictionary Game' illustrates very clearly how dividing a set of possibilities into two, and then this set into two again, then again, can lead very quickly to finding a particular item. Any word can usually be located with a dozen questions of the form: 'Is the word before "G"?' or 'Is it after "D"?' ... But this works only when the items are arranged in some kind of order, such as alphabetical, or numerical. It is, however, just possible that at least some memories may be selected or accessed in this kind of way, by branching search strategies.

In information theory (Shannon and Weaver 1949), information is related mathematically to uncertainty, for it takes more information to specify a particular specific alternative item from many possibilities than from few possibilities. As the number of alternatives increases, so more bits are needed to select one of them. The number of bits required is the logarithm, to the base 2, of the number of alternatives. So for dice, there are six possibilities for a die, and the uncertainty for each face or number on the die is log 6=2.58. For drawing a card from a pack of 52 cards, log 52=5.70. Thus, for the die two or three questions will determine the number, and five or six questions will identify a card.

Many experiments have been aimed at measuring the 'bit rate' for human performance, first defined by W. H. Hake and W. R. Garner in 1951. Their subjects identified positions of a pointer on a linear scale, with various possible positions for the pointer. With five positions the subjects lost no information, but with 10, 20, or 50 alternatives the transmitted information was effectively constant, at about 3.0 bits. People can only identify about nine points on a line; increasing the number of alternatives does not increase the amount of information transmitted. The human bit rate for choices along a single dimension is about 3.0 bits, but this rises with more dimensions (for example, recognizing positions of a dot on a square, with a short exposure time) up to about 8 bits. Long practice may raise the bit rate somewhat.

H. Quastler and V. J. Wulff (cited in Attneave 1959) have estimated bit rates for various human skills. For a pianist playing random notes, the bit rate may be as high as 22 bits per second. The skilled pianist learns to 'chunk' notes into familiar chords — each being a single selection — so his effective performance may be much better. Typing is limited to about 15 bits per second. Speech can be as high as 26 bits per second, though around 18 is normal. It has been estimated that silent reading may be as high as 44 bits per second. Mental arithmetic by a 'lightning calculator' was estimated at about 24 bits per second: about the same as that of a pianist.

The pioneering experiment by Edmund Hick (1952), which measured the 'rate of gain of information' by getting subjects to press a key corresponding to a light, with various numbers of keys and lights, showed that reaction time increases logarithmically as the number of choices (the number of lights and keys, one for each finger) increases. There is, however, a deep problem for this or any other technique for measuring the bit rate for the human nervous system — for we are never quite limited to the alternatives provided by the experimenter. Thus, the subject in Hick's experiment (actually the editor of this Companion!) was not deaf, or blind, to everything except the lights to which he was responding, so that his range of possibilities was always greater than the experimenter knew, or could take into account. Possibly attention serves, consciously or unconsciously, to limit accepted possibilities, to make best use of our limited human bit rate.

(Published 1987)

— Richard L. Gregory

Bibliography
• Attneave, F. (1959). Applications of Information Theory to Psychology.
• Gregory, R. L. (1986). 'Whatever happened to information theory?' In Odd Perceptions.
• Hick, W. E. (1952). 'On the rate of gain of information'. Quarterly Journal of Experimental Psychology, 4.
• Shannon, C. E., and Weaver, W. (1949). The Mathematical Theory of Communication.

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noun
noun, orig US jazz and bop musicians'

1:
a: : a bit of fluff (goods, muslin, mutton, skirt, stuff) a woman or girl. (1847 —) .
J. I. M. Stewart They mustn't quarrel over a bit of skirt (1977).

b: A woman or girl (perh. short for a bit of fluff, goods, etc.). (1923 —) .
B. Goolden If I want a common little bit for a best girl that's my look-out, too (1953).


2: A prison sentence. (1871 —) .
J. H. Smyth The only question was how much of a bit Lucky would get (1951).

3:
a: (little) bit of all right something or someone highly satisfactory; esp. applied to a pretty or obliging woman. (1898 —) .
M. Dickens 'What's she like?'...'The daughter? Bit of all right, from her pictures' (1956).


4: An aggregate of features, way of behaving, etc. characteristic of a particular activity, lifestyle, etc. (1958 —) .
Gandalf's Garden I was originally on the jazz scene and in a terrible state. You know, doing the whole bit, being on the phoney junky trip which nearly every jazz musician was on (1969).

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a single binary digit having the value of either 0 or 1; the smallest unit of information in a binary system. A group of (usually) eight bits comprises a byte, which can represent numbers between 0 and 11111111 in binary (equal to 0 and 255 in decimal). [abbr. for binary digit.]

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For a list of words related to bit, see:

• Building and Machine Parts - bit: cutting or drilling part of tool
• Common Tools and Tool Types - bit: detachable, usu. interchangeable cutting, drilling, or boring part of a drill or other tool, available in various sizes suited to hole desired or specific need
• Drills and Bits - bit: detachable, usu. interchangeable cutting, drilling, or boring part of drill or other tool, available in various sizes suited to hole desired or specific need
• Hardware and Supplies - bit: detachable, usu. interchangeable cutting, drilling, or boring part of tool, available in various sizes suited to hole desired or specific need; drill bit
• Memory and Data Storage - bit: one binary digit, whose value is either zero or one; basic unit of computer memory
• Stagecraft, Production, and Dramatic Structure - bit: short theatrical routine
• Movie People and Show Business - bit: small part for actor, sometimes with a few lines

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See words rhyming with "bit."

  See crossword solutions for the clue Bit.

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Dansk (Danish)
1.
n. - smule, kende

idioms:

• a bit    en smule, en kende
• a bit of    en smule, et stykke
• a little bit    en lille smule, en anelse, et lille stykke
• bit by bit    stykke for stykke, lidt ad gangen
• bit part    lille rolle
• do one's bit for    gøre sin borgerpligt, gøre sin del af arbejdet for
• every bit as good as    præcis lige så god som, nøjagtig lige så god som

2.
n. - bidsel, mundstykke
v. tr. - lægge bidsel på

3.
n. - bit

idioms:

• bit map    bitmap

Nederlands (Dutch)
stukje, beetje, bit, hapje, (aan)deel, scène, boorijzer, schaafbeitel, muntje, bit aandoen, beteugelen

Français (French)
1.
n. - bout, morceau, passage, peu, bout de, (fig) en ruines, bout de temps, un instant, pièce (de monnaie)

idioms:

• a bit    un peu, un morceau de
• a bit of a    un peu de
• bit by bit    petit à petit
• bit part    petit rôle
• do one's bit    fournir sa part d'effort
• every bit as good as    tout aussi bon que
• not a bit    pas du tout, de rien
• not a bit of it    pas le moins du monde (excl)

2.
n. - mors (d'un cheval), (fig, lit) mors, mèche (de vilebrequin), foret (de perceuse), mors (d'une tenaille, d'un étau), ciseau (d'un rabot)
v. tr. - prendre le mors

idioms:

• off the bit    (Comput) en position fermé, ne pas (être) dans son assiette
• take the bit between one's teeth    prendre le mors aux dents

3.
n. - (Comput) bit/chiffre binaire, piste (sur le disque)

idioms:

• bit map    (Comput) carte des couleurs disponibles

Deutsch (German)
1.
n. - Stückchen, Stück, Happen, ein Stückchen, Kleinigkeit

idioms:

• a bit    ein bißchen
• a bit of a    ein bißchen
• bit by bit    nach und nach, Schritt für Schritt
• bit part    Nebenrolle
• do one's bit    seinen Teil beisteuern
• every bit as good as    ebensogut sein wie
• not a bit    überhaupt nicht
• not a bit of it    ganz im Gegenteil

2.
n. - Gebiß, Kandare, Bohrer, Meißel, Schneide, (Mus) Rohrstück bei Blechinstrumenten
v. - Pferd zügeln

idioms:

• off the bit    die Zügel locker halten
• take the bit between one's teeth    (fig) sich [für jmdn./etw.] ins Zeug legen

3.
n. - (EDV) Bit

idioms:

• bit map    Bitmap

Ελληνική (Greek)
n. - τριβέλι, τρυπάνι, χαβιά/στομίδα χαλινού, χαλινάρι, κομματάκι, λιγάκι, στιγμή, άκρη τρυπανιού, (Η/Υ) μπιτ, δυαδικό ψηφίο
abbr. - (Η/Υ) μπιτ, δυαδικό ψηφίο

idioms:

• a bit    λιγάκι
• a bit of    λίγος, κάπως
• a little bit    λίγο
• bit by bit    σταδιακά, λίγο λίγο
• bit map    (Η/Υ) χάρτης δυαδικών ψηφίων (για την απεικόνιση γραμματοσειρών), (τυπογρ.) κουκκίδες φωτοσύνθεσης στοιχείου
• bit part    ασήμαντος θεατρικός ρόλος, ρολάκος
• do one's bit for    κάνω το χρέος μου (για)
• every bit as good as    καθ' όλα ισάξιος με

Italiano (Italian)
pezzetto, morso, punta

idioms:

• a bit    un po', un poco
• a bit of    un po', un poco
• a little bit    un pochino
• a tiny bit    un pizzico
• a tiny bit of    un tantino
• a wee bit    un pizzico
• a wee bit of    un pochino
• be every bit as good as    essere all'altezza di
• bit by bit    a poco a poco
• bit part    parte secondaria
• do one's bit for    contribuire a

Português (Portuguese)
n. - bocado (m) de freio, verruma (f), menor unidade (f) de informação usada pelo computador
abbr. - bit

idioms:

• a bit    um pouco, por pouco tempo
• a bit of    um pouco de
• a little bit    um pouquinho
• a little bit of    um pouquinho de
• a tiny bit    um mínimo
• a tiny bit of    um mínimo de
• a wee bit    um bocadinho (coloq.)
• a wee bit of    um bocadinho de (coloq.)
• be every bit as good as    exatamente como (coloq.)
• bit by bit    aos poucos
• bit part    papel (m) secundário (de ator em filme ou peça)
• do one's bit for    fazer a sua parte (coloq.)

Русский (Russian)
кусочек, сверло, бит

idioms:

• a bit    немного, слегка, чуть-чуть
• a bit of    немного, слегка
• a little bit    чуть-чуть, слегка, чуточку
• a little bit of    немного
• a tiny bit    чуточку
• a tiny bit of    немножко
• a wee bit    чуточку
• a wee bit of    немножко
• be every bit as good as    ничуть не хуже
• bit by bit    мало-помалу
• bit part    эпизодическая роль
• do one's bit for    внести свою лепту во что-либо

Español (Spanish)
1.
n. - trozo, bocado, pedazo, parte

idioms:

• a bit    algo, un poco, un tanto, un trozo
• a bit of a    un poco de, un pedacito de, un poquitín de, un trocito de, un trozo de, un poquito de
• bit by bit    poco a poco, paso a paso
• bit part    papel secundario
• do one's bit    aportar su grano de arena a, poner de su parte
• every bit as good as    valer tanto como
• not a bit    ni un poquitín, de ningún modo
• not a bit of it    ni un poquitín, de ningún modo

2.
n. - freno, barrena, broca
v. tr. - trozar, partir, barrenar

idioms:

• off the bit    soltar las riendas de un caballo para que galope en libertad
• take the bit between one's teeth    desbocarse, rebelarse

3.
n. - bit

idioms:

• bit map    (informática) mapa de bits

Svenska (Swedish)
n. - bit, skär, bett, munstycke, Bit (data), stycke, litet mynt
abbr. - binär siffra

中文（简体）(Chinese (Simplified))
1. 小片, 小段, 小块, 一会儿, 片刻, 少量, 一点点, 老一套

idioms:

• a bit    有点
• a bit of    一点
• a little bit    有点, 稍...
• bit by bit    慢慢地, 渐渐地
• bit part    戏剧电影等的小角色
• do one's bit for    为...尽自己的一份力量
• every bit as good as    完全一样好

2. 嚼口, 咬嘴, 马勒, 钻头, 给上嚼口, 约束, 抑制

3. 字节

idioms:

• bit map    位图, 位映像

中文（繁體）(Chinese (Traditional))
1.
n. - 小片, 小段, 小塊, 一會兒, 片刻, 少量, 一點點, 老一套

idioms:

• a bit    有點
• a bit of    一點
• a little bit    有點, 稍...
• bit by bit    慢慢地, 漸漸地
• bit part    戲劇電影等的小角色
• do one's bit for    為...盡自己的一份力量
• every bit as good as    完全一樣好

2.
n. - 嚼口, 咬嘴, 馬勒, 鑽頭
v. tr. - 給上嚼口, 約束, 抑制

3.
n. - 位元組

idioms:

• bit map    點陣圖, 位映射

한국어 (Korean)
1.
n. - 조금, 작은 조각, 잠깐, 잔돈, 단역, 징역

idioms:

• a bit    약간
• a bit of    한 조각의, 조금의
• a little bit    약간 , 조금
• a little bit    작은, 대수롭지 않은
• do one's bit for    본분을 다하다

2.
n. - 재갈, 날, 송곳
v. tr. - 재갈을 물리다, 억제하다

3.
n. - 비트(정보량의 단위)

日本語 (Japanese)
n. - 小片, 少量, 少し, 12セント半, 小銭, はみ, 刃, かみ合わせ, ビット

idioms:

• a bit    少しだけ
• a bit of    少量の
• a bit of a laugh    ちょっとしたおふざけ
• a bit thick    ひどすぎる
• bit by bit    少しずつ
• bit part    端役
• do one's bit for    寸分を尽くす

العربيه (Arabic)
‏(الاسم) جزء, قطعه, أداة تخريم (اختصار) عدد ثنائي‏

עברית (Hebrew)
n. - ‮משהו, קצת, חתיכה, מטבע קטן‬
n. - ‮מתג (בפי הסוס), מקדח, שיני המפתח‬
v. tr. - ‮שם רסן בפי הסוס, ריסן‬
n. - ‮סיבית, ביט, יחידת ההצפנה הקטנה ביותר של נתון במחשב‬

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