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. S

    Transistor cant understand even a bit

    i can't understand the transistor completely i can understand how it works but this stupid conventional current is confusing me completely please can anyone give a lengthy explanation on working of transistor CE CB CC types. i don't understand all these types of transistor i.e how current...
  2. G

    A layman a bit scared of the LHC (as always)

    Hello there, I've been here before to ask for help with my fears about the LHC a while ago. Suffice to say I eventually overcame them thanks to the help from some members of this forum and that of Michaelangelo Mangano of CERN. However recently I've decided to revisit the old LHC Defense forums...
  3. P

    Towers of hanoi induction- slight bit i don't understand

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  4. L

    A bit about differential equations

    For first order linear differential equations when is it alright to use the dy/y-b/a = -adt form and when you must use the integration factor technique? In general i was able to obtain a solution using both methods. Also, how do i draw a direction field which contains both t and y variables...
  5. lisab

    This is so wrong And just a little bit funny

    This is so wrong! And just a little bit funny! http://www.msnbc.msn.com/id/32581670/ns/today-today_pets_and_animals/displaymode/1247/?beginSlide=1" I have to admit, I did chuckle at some of these pix :redface:. Poor, poor doggies.
  6. B

    Solve 3^{2010}+15^{2010} Divided by 13 | Help for Math Struggler

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  7. P

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  8. P

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  9. S

    Schools My high school career, theres a bit of a problem .

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  10. T

    Now i find myself in a bit of an indecision

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  11. E

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  12. A

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  13. L

    Volume of rotation - my answer seems off a bit

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  14. C

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  15. S

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  16. Z

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  17. T

    QM- A bit of manipulation of expectation values.

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  18. W

    Need a bit of help with arrow speed.

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  19. S

    Engineering Design a 2 bit multiplier circuit

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  20. A

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  21. I

    Centripetal and Tangential Acceleration of drill bit

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  22. W

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  23. G

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  24. M

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  25. S

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  26. M

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  27. C

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  28. F

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  29. olgranpappy

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  30. I

    Communication Problems (Filters, BW, Bit rate, FM)

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  31. Y

    Bit foggy on this trig question

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  32. B

    Question regarding digital communications and bit error probability.

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  33. D

    Relearning a little bit of trig

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  34. I

    Is the Universe Fundamentally Composed of Information?

    Physicists have anxiously devised one philosophical interpretation of quantum mechanics after another. http://pawst.com/post/586113-new-scientist-in-the-beginning-was-the-bit" with a macroscopic apparatus in the laboratory, which eliminates all possibilities but one.
  35. I

    Deriving Bit Error Rates for different diveristy tecniques

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  36. R

    Designing a 4-bit ALU: Functions & Solutions for a Microprocessor

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  37. N

    I'm having a bit of a decision crisis

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  38. M

    Confused just a little bit though difference between (x,y), and <x,y>

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  39. B

    A Pickup Truck and a bit of Friction

    Homework Statement A pickup truck with a steel bed is carrying a steel file cabinet. If the truck's speed is 27 m/s, what is the shortest distance (m) in which it can stop without the file cabinet sliding? (Use µs = 0.8 for the coefficient of static friction of steel on steel.) Homework...
  40. R

    Can Two 8-bit Adders Be Used to Construct a 16-bit 2's Complement Adder?

    16 bit 2's complement adder. Due tomorrow! You are given two adders. Each adder has two 8-bit operand inputs and a 1-bit carry input. Each adder calculates the sum of the two 8-bit 2's complement operands and the 1-bit carry and outputs an 8-bit sum and a 1-bit 2's complement overflow bit...
  41. D

    Synchronized random bit generator

    Is it possible to construct 2 devices which simultaneously generate (the same) random bits indefinitely? No matter how far apart spatially they are. And I don't mean a pseudorandom number generator with the same seed. I mean something like sharing entangled particles, but without the need to...
  42. L

    Effective bit depth of averaged pixels?

    Hello, I am trying to figure out how many effective bits of color depth are carried in the red channel of a number of averaged pixels. For instance, a single 24 bit pixel carries 8 bits per color channel (RGB). Therefore, you can generate 2^8 = 256 red levels, 2^8 = 256 green levels...
  43. R

    Finding the Identity and Inverse of the Operation *

    "Define a * b, for a,b \in R by a * b = ab+a+b. What we just have done is defined a new operation *, in terms of the well known ones multiplication and addition." Is there a real number which is the identity under the operation * ? Lets call this number e. A number for which a * e = e * a...
  44. B

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    Ok, I have been to these forums a lot in the past year or so and I have learned a lot and asked a lot. But recently my past year has just been a drag - it is my first year in university and I know that some or maybe even majority will say it is only first year. But I don't think it is that, I...
  45. D

    Struggling with Integration: A Call for Assistance

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  46. F

    Bit shifting and bitwise operators

    Homework Statement folks, I have a small problem understanding a function as to what its doing: I have run this program in C++. I will comment the lines of code as per my understanding. Your insight would be useful unsigned int myfunc(unsigned int n) { // for n here I took 1200...
  47. E

    What's wrong with a bit of global warming?

    It's seems to be the accepted thing that global warming is bad, but is it such a bad thing? The dinosaurs certaintly preferred a more warmer climate. Look at the facts:- 1. The ice caps are melting - so what? What we lose on the south pole we gain on the north pole, we might lose a...
  48. M

    [Recurrence Relation]three conscutive 0's in bit string

    Homework Statement Find a recurrence relation for the number of bit strings of length n that contain three consecutive 0s. The Attempt at a Solution Divide the bit strings into two condition: one that have three consecutive 0s, another that does not. Let x_i denote the bit strings of...
  49. M

    Is a Love for Math a Prerequisite for a Successful Physics Major?

    Long time lurker, first time poster. I'd like to preface this by saying that I've spent many an hour glued to my monitor due to the very thoughtful and often eloquent posts on this forum. I am an undergraduate physics major who until recently was an economics major. This semester I began...
  50. F

    Engineering Cr and lr circuits help exam in a bit and i'm stuck

    cr and lr circuits help.. exam in a bit and I'm stuck! okay so here's my question : how is the peak voltage across the resistance (in a cr circuit) or the induction (in an rl circuit) = \pmV_{m}/(1-e^{-T/2\tau}) V_{m} is the max voltage of the pulse train. the m denotes max both...
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