What is Bit: Definition and 398 Discussions

The bit is the most basic unit of information in computing and digital communications. The name is a contraction of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represented as either "1"or"0", but other representations such as true/false, yes/no, +/−, or on/off are commonly used.
The correspondence between these values and the physical states of the underlying storage or device is a matter of convention, and different assignments may be used even within the same device or program. It may be physically implemented with a two-state device.
The symbol for the binary digit is either "bit" per recommendation by the IEC 80000-13:2008 standard, or the lowercase character "b", as recommended by the IEEE 1541-2002 standard.
A contiguous group of binary digits is commonly called a bit string, a bit vector, or a single-dimensional (or multi-dimensional) bit array.
A group of eight binary digits is called one byte, but historically the size of the byte is not strictly defined. Frequently, half, full, double and quadruple words consist of a number of bytes which is a low power of two.
In information theory, one bit is the information entropy of a binary random variable that is 0 or 1 with equal probability, or the information that is gained when the value of such a variable becomes known. As a unit of information, the bit is also known as a shannon, named after Claude E. Shannon.

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  1. B

    Feeling a bit lost with an MPhys degree

    I'm in the penultimate year of my MPhys degree and I am on track to get a 2.1 I am good friends with the people in the year above me and speaking to them has made me feel a little lost re: careers. Medical physics is something that really interests me, and something I was planning on...
  2. R

    Isn't M-theory and the multiverse idea a bit discouraging?

    I have been reading about the multiverse idea recently and when I came to think of it , as much as I find it extremely interesting, isn't it a bit discouraging as well? I mean, if there was "time" before the big bang and if there are infinite number of other "bubble" universes in the "11th...
  3. K

    Calculating Energy Per Bit from Symbols Constellation

    In general, if I have a constellation of symbols, how can i calculate the energy por bit? I think I should calculate the area of figure which is formed linking external points in the space signal and divide it for the numer of bit compose the symbols. Right?
  4. K

    MATLAB Bit of help with piecewise and parametric functions in MATLAB?

    Hi guys, after using the forum for ages for help I decided to make an account, so hopefully I might be able to contribute something as well, who knows :) I'm a first timer with MATLAB and have been set an assignment. I'm completely stuck on question one: The following image shows my code and...
  5. S

    Mathematica I need a little bit help about mathematica

    Hello, my problem is that I could not be able to find to separate the roots with the command of FindRoot. Altough I have 2 non-linear equations, I can solve these with FindRooot, but I'd like to have separetely the roots I mean independent roots each other (x apart and y apart). I wonder if i...
  6. H

    Exploring 8-bit BCD and Integers: How Many Can be Represented?

    Homework Statement Suppose a computer has 8-bit words. How many different integers can be represented (in decimal) in a single word if the integers are represented in binary coded decimal(BCD)? Homework Equations BCD= Binary Coded DecimalThe Attempt at a Solution BCD is coded in 4 bits so...
  7. R

    Game Theory a problem which is a bit similar to the Impossible Puzzle

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  8. J

    I've gotten stuck with a bit of dirac notation calculation?

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  9. P

    A bit OffTopic: ideas for astronomy/astrophysics gift pack

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  10. J

    A straightforward matrix eigenvectors/values problem, I'm a bit rusty?

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  11. D

    Internship stretched a bit from my field

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  12. E

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  13. J

    Do you think Newton is a bit overrated?

    I admire Newton's work and agree that he was a great scientist. He came up with many new original ideas. But there are many other scientists who are equally or perhaps more great who are not held as high as Newton. Some of the names which I could think of off hand are: Archimedes, Leibniz. My...
  14. S

    A jumble of basic SUSY questions (i.e. a bit confused and seeking help)

    So, I've been tasked to learn SUSY in a small time span (few weeks) and I've made some progress but I'm a little stumped on how deeply I should go into things while still making reasonable progress (get to phenomenology, etc). First of all, most primers seem to gloss over the algebra or go...
  15. Nick666

    Clarifying Mathematical Confusion: The Truth About 1010101010

    My math is rusty so please tell me 1010101010 does not equal (((1010)10)10)10 , right ?
  16. M

    Need a Tiny Bit of Help with 555 Oscillator Frequency Formula

    With regards to this http://www.electronics-tutorials.ws/waveforms/555_oscillator.html, I figured out how to get t2 fine, but I have a problem figuring out how to get t1...I know when the negative-going waveform at pin 2 crosses Vcc/3, pin 3 goes to Vcc, and pin 7 gets internally disconnected...
  17. S

    2 Bit Adder: Inputs 0,1,0,1 Outputs

    Hello! I've been working out the truth table to a logic gate which I've been told is a 2 Bit Adder. The inputs, in the order of the truth table below are 0, 1, 0, 1. Inputs: Outputs: 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 1 0 0 0 0 1 0 0 1 0 0 1 0 0 0 0 1 0 0 1 1 1 0 0 0 1 1 1...
  18. B

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  19. V

    Creating a Bit Detector with Mealy Machine: State Diagrams & Tables

    Homework Statement I have to make a scheme of a bit detector that detects the bit "1101" with a Mealy Machine. So I have made the following state diagram and state table(picture 1 and picture 2) http://img215.imageshack.us/g/picture1jf.png/" Now I don't know what happens in picture 3. How...
  20. P

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    Homework Statement This problem is for a cordless drill. http://img718.imageshack.us/img718/8531/drill1.jpg Homework Equations [PLAIN][PLAIN]http://img442.imageshack.us/img442/3511/drill2.jpg where N denotes number of teeth w denotes angular velocity The Attempt at a...
  21. C

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  22. M

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  23. M

    Simple Integral. I'm a bit rusty.

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  24. Saladsamurai

    Fortran Which FORTRAN Compilers are Compatible with Windows 7 32-bit?

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  25. A

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  26. Z

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  27. M

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  28. M

    Using 4x4 bit multipiers to do an 8x8 bit multiply

    Hi How would I use 4x4bit multipliers to calculate an 8x8 bit multiply? Thanks
  29. A

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  30. S

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    Hi guys, recently I am reading Kleppner's Mechanics about center of mass, well, I am always a fairly fast learner, but I really got stick here. you see, in the page 119 example 3.3 (in short, a rod with nonuniform density ) let Q(x) be the function density of location vector it said...
  31. T

    Are Electromagnetic Fields Considered Spinors in Geometric Algebra?

    Hi, I'm trying to teach myself a bit about spinors, mainly from reading about geometric algebra. There is something that I can't figure out though. According to GA, spinors are elements of the even graded subalgebra, so scalars, bivectors and so on. But the electromagnetic field is a bivector...
  32. F

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  33. Z

    Bit of a Frivolous Question - Doing Math in Pen?

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  34. S

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  35. J

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  36. S

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  37. T

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  38. K

    Learn a bit more about triality of SO

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  39. F

    A four bit adder logic circuit block diagram

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  40. M

    Spring, resonance frequency and a bit of fun

    Homework Statement The Hungarian national highway M7 is made of concrete blocks 4m long. The joints have a small gap. Józsi have a mass of 80 kg. He owns a Polski Fiat, which is lowered by 10 cm when he sits in. At what speed would Józsi's car disintegrate? Homework Equations v =...
  41. M

    A Bit of Help With Peak Current Flowing with Inductor Please

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  42. I

    Engineering Creating a 4 bit full adder logic circuit

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  43. N

    How Can Bit Operations Simplify Conditional Checks in C?

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  44. N

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  45. N

    Efficiently Count Bits in 32-bit Integers using Bit Operations

    Hi all, I am wondering is there a way to count the number of bits to the left or right of a given 1 in a 32-bit integer? For example, if I give the function the number 32 = 0b100000, there are 5 bits to the right of the 1 and hence, 26 bits to the left of the 1. The catch is, is there a way...
  46. Vectronix

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  47. M

    Introduction, a bit long and Advice

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  48. Ivan Seeking

    News A bit of irony regarding Obama

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  49. D

    How do I compute the moment in my statics assignment?

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  50. F

    Injective Affine Linear Map for (Z/2Z)^3 to (Z/2Z)^3 Sending (1,1,1) to (0,0,0)

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