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{{Short description|Computer architecture bit width}}
{{Computer architecture bit widths}}
In [[computer architecture]], '''32-bit computing''' refers to computer systems with a [[Central processing unit|processor]], [[computer memory|memory]], and other major system components that operate on data in a maximum of 32-[[bit]] units.<ref name="PCMProsise1995">{{Cite magazine |last=Prosise |first=Jeff |date=
32-bit designs have been used since the earliest days of electronic computing, in experimental systems and then in large [[mainframe computer|mainframe]] and [[minicomputer]] systems. The first hybrid 16/32-bit [[microprocessor]], the [[Motorola 68000]], was introduced in the late 1970s and used in systems such as the original [[Apple Macintosh]]. Fully 32-bit microprocessors such as the [[HP FOCUS]], [[Motorola 68020]] and [[i386|Intel 80386]] were launched in the early to mid 1980s and became dominant by the early 1990s. This generation of personal computers coincided with and enabled the first [[
==Range for storing integers==
A 32-bit [[processor register|register]] can store 2<sup>32</sup> different values. The [[range (computer programming)|range]] of [[integer]] values that can be stored in 32 bits depends on the [[Integer (computer science)#Value and representation|integer representation]] used. With the two most common representations, the range is 0 through [[4,294,967,295]] (2<sup>32</sup> − 1) for representation as an ([[signedness|unsigned]]) [[binary number]], and −2,147,483,648 (−2<sup>31</sup>) through [[2,147,483,647]] (2<sup>31</sup> − 1) for representation as [[two's complement]].
One important consequence is that a processor with 32-bit [[memory address]]es can directly access at most 4 [[Gibibyte|GiB]] of [[Byte addressing|byte-addressable]] memory (though in practice the limit may be lower).
==Technical history==
[[File:XC68020 top p1160084.jpg|thumb|Motorola 68020 prototype from 1984. It features a 32-bit ALU and 32-bit address and data buses.]]
The world's first stored-program [[electronic computer]], the [[Manchester Baby]], used a 32-bit architecture in 1948, although it was only a [[proof of concept]] and had little practical capacity. It held only 32 32-bit words of RAM on a [[Williams tube]], and had no addition operation, only subtraction.
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==See also==
* [[Fifth generation of video game consoles|History of video games (32-bit era)]]
* [[Word (computer architecture)]]
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