https://www.chessprogramming.org/index.php?title=Bit&feed=atom&action=historyBit - Revision history2024-03-29T04:48:12ZRevision history for this page on the wikiMediaWiki 1.30.1https://www.chessprogramming.org/index.php?title=Bit&diff=10903&oldid=prevGerdIsenberg: Created page with "'''Home * Programming * Data * Bit''' [[PDP-6 Memory#FlipF..."2019-02-28T16:28:53Z<p>Created page with "'''<a href="/Main_Page" title="Main Page">Home</a> * <a href="/Programming" title="Programming">Programming</a> * <a href="/Data" title="Data">Data</a> * Bit''' <a href="/File:Flipflop6as.jpg" title="File:Flipflop6as.jpg">border|right|thumb|link=http://ljkrakauer.com/LJK/essays/bits.htm| [[PDP-6</a> Memory#FlipF..."</p>
<p><b>New page</b></p><div>'''[[Main Page|Home]] * [[Programming]] * [[Data]] * Bit'''<br />
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[[FILE:flipflop6as.jpg|border|right|thumb|link=http://ljkrakauer.com/LJK/essays/bits.htm| [[PDP-6]] [[Memory#FlipFlop|flip-flop]] stores one bit <ref>[http://ljkrakauer.com/LJK/essays/bits.htm Bits] by [[Lawrence J. Krakauer]]</ref> ]]<br />
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'''Bit''',<br/><br />
the [https://en.wikipedia.org/wiki/Units_of_information basic unit] of [https://en.wikipedia.org/wiki/Information information] in [https://en.wikipedia.org/wiki/Information_theory information theory] and [https://en.wikipedia.org/wiki/Computing computing] - a binary digit, either 0 or 1 in the arithmetical sense, 'false' or 'true' in the boolean sense, black (dark) or white (light) as a [[Color]] in [[Chess]], etc.. <br />
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=Quote=<br />
by [[Claude Shannon]] in ''A Mathematical Theory of Communication'' 1948 <ref>[[Claude Shannon]] ('''1948'''). ''A Mathematical Theory of Communication'', [http://cm.bell-labs.com/cm/ms/what/shannonday/shannon1948.pdf pdf reprint]</ref>:<br />
The choice of a logarithmic base corresponds to the choice of a unit for measuring information. If the base 2 is used the resulting units may be called binary digits, or more briefly bits, a word suggested by [https://en.wikipedia.org/wiki/John_Tukey J. W. Tukey]. A device with two stable positions, such as a [https://en.wikipedia.org/wiki/Relay relay] or a [[Memory#FlipFlop|flip-flops]] circuit, can store one bit of information. <br />
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=Aggregations= <br />
Aggregations of bits are used to code numbers, integers or floating point values, characters, codes and sets. Four bits are called a [[Nibble]] with 16 states - written as one hexadecimal digit <span style="background-color: #d6d6d6;">{'0'..'9', 'A'-'F'}</span>. A group of eight Bits, two Nibbles or one [[Byte]] with 256 states (e.g. unsigned numbers 0..255) is most often the smallest addressable unit in computer architectures. [[Bitboards]] are set-wise bit aggregations which covers all 64 [[Squares|squares]] of a [[Chessboard]].<br />
<span id="BitwiseArithmetic"></span><br />
=Bitwise Arithmetic= <br />
Bitwise addition (Modulo 2) and subtraction with aggregations of Bits without overflows can be applied by bitwise [[General Setwise Operations#ExclusiveOr|exclusive or]]:<br />
{| class="wikitable"<br />
|-<br />
! a <br />
! b <br />
! a xor b <br />
|-<br />
| style="text-align:center;" | 0 <br />
| style="text-align:center;" | 0 <br />
| style="text-align:center;" | 0 <br />
|-<br />
| style="text-align:center;" | 0 <br />
| style="text-align:center;" | 1 <br />
| style="text-align:center;" | 1 <br />
|-<br />
| style="text-align:center;" | 1 <br />
| style="text-align:center;" | 0 <br />
| style="text-align:center;" | 1 <br />
|-<br />
| style="text-align:center;" | 1 <br />
| style="text-align:center;" | 1 <br />
| style="text-align:center;" | 0 <br />
|}<br />
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=See also= <br />
* [[Nibble]]<br />
* [[Byte]]<br />
* [[Word]]<br />
* [[Double Word]]<br />
* [[Quad Word]]<br />
* [[Bitboards]]<br />
* [[BitScan]]<br />
* [[Bit-Twiddling]]<br />
* [[General Setwise Operations]]<br />
: [[General Setwise Operations#TheLeastSignificantOneBitLS1B|Least Significant One Bit]]<br />
: [[General Setwise Operations#TheMostSignificantOneBitMS1B|Most Significant One Bit]]<br />
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=External Links= <br />
* [https://en.wikipedia.org/wiki/Bit Bit from Wikipedia]<br />
* [https://en.wikipedia.org/wiki/Bit_%28disambiguation%29 Bit (disambiguation) from Wikipedia]<br />
* [https://en.wikipedia.org/wiki/Nat_%28information%29 Nat (information) from Wikipedia]<br />
* [https://en.wikipedia.org/wiki/Ban_%28information%29 Ban (information) from Wikipedia]<br />
* [https://en.wikipedia.org/wiki/Qubit Qubit from Wikipedia]<br />
* [https://en.wikipedia.org/wiki/Shannon_(unit) shannon (unit) from Wikipedia]<br />
* [http://ljkrakauer.com/LJK/essays/bits.htm Bits] by [[Lawrence J. Krakauer]]<br />
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=References= <br />
<references /><br />
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