Bit Definition and 398 Threads

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. K

    Re: MIPS - Making a 64 bit number when you only have 32 bit register support

    Hey guys I've been working on this program for just over a week now and I just can't seem to find any way around my problem. The problem I'm having is: I'm trying to add 32 bit numbers together and if there is an overflow then I'd like to find a way to output the result as a 64 bit number. I...
  2. J

    How to Compile PROPEP for 32 Bit Systems?

    I am trying to compile PROPEP for 32 bit systems. (Martin-Marietta FORTRAN program for chemical equilibrium) It was originally written for IBM professional FORTRAN version 1.00 I can compile with the IBM 1.00, so I know my source code is valid. I have tried G77 with loads of errors...
  3. K

    MIPS - Making a 64 bit number when you only have 32 bit register support

    Hey guys I've been working on this program for just over a week now and I just can't seem to find any way around my problem. The problem I'm having is: I'm trying to add 32 bit numbers together and if there is an overflow then I'd like to find a way to output the result as a 64 bit number...
  4. DHF

    Upgrading Windows 7 (32 bit to 64)

    Greetings, I currently have a laptop with Windows Home 7 32 bit. I would like to move to 64 bit so I can upgrade the RAM but I would rather not start from scratch. is there a way to load the 64 bit version onto my laptop without wiping out my current programs and settings? any info you...
  5. bohm2

    What is the relationship between matter and information?

    "It from bit" or "Bit from it" I've always had some difficulties understanding the whole concept of information: Is matter really just information? Does one mean just our information about matter? Isn't all information embodied in some more basic "physical" stuff? Doesn't information...
  6. Whovian

    Python Efficient Factorial Calculation in Python: Recursive vs. Iterative Methods

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  7. P

    Is There a Way to Turn My Life Around After So Much Struggle?

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  8. B

    Fourier Transform help (bit )

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  9. C

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  10. H

    I need a bit of help rearranging this equation

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  11. C

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  12. S

    Still a bit confused about electron orbitals?

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  13. P

    I'm a bit confused about rotation and reflection matrices

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  14. B

    A bit of help with a capacitor problem

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  15. 9

    Find points of inflection from f''(x) = 12x + 18? A bit confused

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  16. I

    Work, Power, Frictional Force - seems a bit tricky for me

    Homework Statement A highway goes up a hill, rising at a constant rate of 1.00 m for every 48 m along the road. A truck climbs this hill at constant speed vup = 19 m/s, against a resisting force (friction) f equal to 1/24 of the weight of the truck. Now the truck comes down the same hill...
  17. N

    A bit of a problem with the liberal arts department

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  18. turbo

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  19. G

    How Is Field Strength Equal to Potential Gradient in Electric Fields?

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  20. H

    Find the bit string for the following sets.

    Homework Statement The a universal set: u = {1,2,3,4,5,6,7,8,9,10} 1) Find the bit string for b = {4,3,3,5,2,3,3,} 2) Find the bit string for the union of two sets. Homework Equations 1)Would I first begin this problem by realizing that set b is the same as {2,3,4,5}? The...
  21. H

    How can I compare bits and perform bit shifts in SystemVerilog?

    Hi, i am trying to do a bit shift in systemverilog and compare the bit. For example: i give a input A=011. Then the input will compare with another digital that i have already setup in fsm like 010. Now it will do the compare, 0 to 0---> bitmatch=1 1 to 1 ---> bitmatch=1 1 to 0 ---> bitmatch=0...
  22. R

    Courses Is Computer Science the course for me (sorry, a bit extensive)?

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  23. P

    Can Structural Induction Prove Bit String Relationships?

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  24. A

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  25. C

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  26. K

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  27. B

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  28. M

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  29. C

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  30. K

    Engineering 2 bit by 1 bit multiplier circuit

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  31. S

    A little bit of help rearranging and equation

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  32. A

    Creating a 4 Bit Calculator: Add, Subtract, Multiply & Divide

    Hi! This is a great forum and I've been using it for help for a while so thought I would finally sign up. Anyway my group is making a 4 bit binary calculator for a course in my second semester and we're am having a few issues. The main restriction is that we can only use basic gates to...
  33. C

    Most significant bit (MSB) in ASCII code

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  34. G

    Typical Surface Finish of Twist Drill Bit

    Dear All, I am looking for the typical surface finish (surface roughness) of a 5 mm hole made by a twist drill bit. Thankssssss GLO
  35. F

    Libsvm problem in make function with windows7 (64 bit)

    i tried to run libsvm several times but i failed, I've visualc++ i do this mex -setup Welcome to mex -setup. This utility will help you set up a default compiler. For a list of supported compilers, see http://www.mathworks.com/support/compilers/R2011a/win64.html Please choose your compiler...
  36. Pengwuino

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  37. M

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    Hi, This isn't so much a coursework question, but a 'where to go from here' question. But because I'm not in college, I figured it doesn't really belong in the academic guidance forum. But anyways, on to my question. Currently, I'm finishing up a 5-week precalculus course at a local...
  38. Y

    Velocity of proton following a helical path? need a bit of help

    velocity of proton following a helical path?? need a bit of help Homework Statement A proton with an initial velocity given by (4.0 + 3.0 + 3.0)(105 m/s) enters a magnetic field given by (0.62 T). Describe the motion of the proton. The proton will follow a helical path with a velocity of...
  39. G

    Studying Is studying a little bit of statistics worth it?

    I'm going to be a senior in high school next year, and I'm thinking about self-studying AP Statistics. I want to be some sort of mathematician or physicist, and I am thinking that having the equivalent of a first-year course in college statistics will significantly broaden my career choices and...
  40. James889

    Bandwidth vs Bit Rate: What's the Difference?

    Hi, I never really understood this. What are the differences between bandwidth and bit rate ? I understand that they describe the same thing, yet are completely different. How are these related?
  41. T

    Bit rate, symbol rate and sampling in LTE

    Hi guys, I have a problem in understanding LTE. LTE is the long term evolution 4G technology. The LTE requirement is 100 Mbps with 1.3, 2.5, 5, 10, 15 and 20 MHz for 128, 256, 512, 1024, 1536 and 2048 subcarriers. Each bandwidth corresponds to each number of subcarriers. My problem here...
  42. B. Elliott

    Welcome Back! Reflecting on Deployment and the Joy of Homeport

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  43. J

    I am a bit confused at orthonormal tetrad in General Relativity

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  44. H

    8 bit adder/sub with 4 bit ripple adder and muxes only

    Hi I'm having trouble with coming up with a minimal solution to this problem: create a 8 bit adder/sub using only one 4 bit ripple carry adder and muxes. This is what I'm thinking but I don't know how to make it any bit simpler: We can calculate the sum of first 4 bits using the ripple carry...
  45. B

    What Is 128-Bit and 256-Bit Encryption?

    Can anyone please explain me what's 128-bit and 256-bit encryption in layman's word (but bit in detail please). (I am a mechanical Engg. and have least knowledge on security aspects of IT). Thnx.
  46. MathematicalPhysicist

    Python Tinkering a little bit with Vpython.

    I thought to write a naive simulation of an inflated ball, I am not sure how to implement this by Vpython. I mean I want to see it gradually inflating minute by minute. This is the code I wrote but I don't know how to add to it a timer. from visual import *...
  47. B

    Bit confused about the geometric series

    I'm confused about the sum of the geometric series: \sum ar^{n-1} = \frac{a}{1-r} when |r|<1 but if you have a series like: \sum (1/4)^{n-1} the sum is: \frac{1/4}{1-(1/4)} should't it be \frac{1}{1-(1/4)} because there is no a value?
  48. K

    How Do You Solve Lagrange Multipliers with Complex Constraints?

    1. Use the method of Lagrange multipliers to nd the minimum value of the function: f(x,y,z) = xy + 2xz + 2yz subject to the constraint xyz = 32. I understand the method how Lagranges Multipliers is donw done but seem to have got stuck solving the Simultaneous Equations involving the...
  49. J

    Just stuck on the last bit integral

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  50. M

    What is the Kinetic Energy of a 3000lb Car Traveling at 60mph?

    Homework Statement what is the kinetic energy of a 3000lb car traveling at a 60mph (pounds are not units of mass) Homework Equations KE=1/2* mass * velocity ^2 The Attempt at a Solution pounds are the units of force but to calculate the mass I am missing some data unless I'm...
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