Difference between revisions of "Word"

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[[Category:Computer Architecture]]
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[[Category:Computer Architecture]]{{Chris Tyler Draft}}
 
== Hardware Word ==
 
== Hardware Word ==
  
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The word size is usually associated with the size of general-purpose [[Register|registers]] and the amount of data read from or written to memory at one time.
 
The word size is usually associated with the size of general-purpose [[Register|registers]] and the amount of data read from or written to memory at one time.
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== Common Names for Various Word Sizes ==
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== Byte ==
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A byte is a collection of eight '''bits'''. It is a convenient size for use with many small character sets such as [[http://czyborra.com/charsets/iso646.html ASCII]], [[http://czyborra.com/charsets/iso8859.html ISO8859]], and [http://czyborra.com/charsets/iso646.html#EBCDIC EBCDIC]], and can also be used with the [[http://czyborra.com/utf/#UTF-8 UTF-8]] encoding of Unicode. It is often viewed as the smallest hardware word size that makes sense for general-purpose computing.
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Most computers with larger hardware word sizes continue to rank memory, storage, and data sizes in bytes (or prefixed multiples of bytes) for comparability. For example, an x86_64 system will be advertised as having "16 gigabytes" of memory instead of "4 gigawords".
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== Octet ==
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Another name for [[#Byte]], commonly used in telecommunication standards and in French.
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== Nibble ==
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A nibble (or nybble) is a half-byte, corresponding to one hexadecimal or BCD digit.

Revision as of 10:19, 7 January 2014

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This is a draft only!
It is still under construction and content may change. Do not rely on this information.

Hardware Word

A word is the group of bits normally managed by a processor. The word size is a distinguishing feature of a processor, and is typically a power-of-two multiple of eight bits (8, 16, 32, or 64 bits), although some rare or early processors used different word sizes.

The word size is usually associated with the size of general-purpose registers and the amount of data read from or written to memory at one time.

Common Names for Various Word Sizes

Byte

A byte is a collection of eight bits. It is a convenient size for use with many small character sets such as [ASCII], [ISO8859], and EBCDIC], and can also be used with the [UTF-8] encoding of Unicode. It is often viewed as the smallest hardware word size that makes sense for general-purpose computing.

Most computers with larger hardware word sizes continue to rank memory, storage, and data sizes in bytes (or prefixed multiples of bytes) for comparability. For example, an x86_64 system will be advertised as having "16 gigabytes" of memory instead of "4 gigawords".

Octet

Another name for #Byte, commonly used in telecommunication standards and in French.

Nibble

A nibble (or nybble) is a half-byte, corresponding to one hexadecimal or BCD digit.