32-bit

Processors
1-bit	4-bit	8-bit	12-bit	16-bit	18-bit	24-bit	31-bit	32-bit	36-bit	48-bit	60-bit	64-bit	128-bit
Applications
		8-bit		16-bit				32-bit				64-bit
Data sizes
bit   nibble   octet   byte
halfword   word   dword   qword
IEEE floating-point standard
Single precision floating-point format (32-bit)  Double precision floating-point format (64-bit)  Quadruple precision floating-point format (128-bit)

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 are the norm.

The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GiB 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.

Architecture

Prominent 32-bit instruction set architectures include the IBM System/360, the DEC VAX, the ARM, the MIPS, and the Intel IA-32.

Images

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

Alternatively it may refer to 32-bit per channel rather than 24-bit colour + 8-bit alpha. 32-bit per channel images are used to represent values brighter than white; these values can then be used to more accurately retain bright highlights when either lowering the exposure of the image or when it is seen through a dark filter or dull reflection.

An example of this is the reflection seen in an oil slick; even though the reflection is only a fraction of that seen in a mirror surface, the reflection of highlights can still be seen as bright white areas, not dull grey shapes.

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.

See also

• 16-bit
• 16-bit application
• 32-bit application
• 64-bit
• History of video games (32-bit era)
• Word (data type)
• Physical Address Extension (PAE)

References

• Gwennap, Linley (16 February 1995). "Intel’s P6 Uses Decoupled Superscalar Design". Microprocessor Report.

External links

• HOW Stuff Works "How Bits and Bytes work"
• Ken Colburn on LockerGnome.com: 32-Bit Vs. 64-Bit Windows