32-bit

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In computer architecture, 32-bit integers, memory addresses, or other data units are those that are at most 32 bits (4 octets) wide. Also, 32-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size.

32-bit is also a term given to a generation of computers in which 32-bit processors were the norm.

The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295 or −2,147,483,648 through 2,147,483,647 using two's complement encoding. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory.

The external address and data buses are often wider than 32 bits but both of these are stored and manipulated internally in the processor as 32-bit quantities. For example, the Pentium Pro processor is a 32-bit machine, but the external address bus is 36 bits wide, and the external data bus is 64 bits wide.

[edit] Architecture

Prominent 32-bit processors include the IBM System/360, the DEC VAX, Motorola 68000 series and the Intel 80386 series. (The Motorola 68000 is externally 16 bits long; however, it has 32-bit general purpose registers, arithmetic units, and is forwards-compatible with all 32-bit software.)

[edit] Images

In digital images/pictures, 32-bit can refer to 24-bit truecolor images with an 8-bit alpha channel.

[edit] 32-bit file format

A 32-bit file format is a binary file format for which each elementary information is defined on 32 bits (or 4 Bytes). An example of such a format is the Enhanced Metafile Format.

[edit] See also

• word (computing)
• 16-bit
• 16-bit application
• 32-bit application
• History of video games (32-bit era)
• 64-bit

[edit] External links

• HOW Stuff Works "How Bits and Bytes work"