16-bit application

A 16 bit application is any software written for MS-DOS, OS/2 1.x or early versions of Microsoft Windows which originally ran on the 16-bit Intel 8088 and Intel 80286 microprocessors. Such applications used a 20-bit or 24-bit segment or selector-offset address representation to extend the range of addressable memory locations beyond what was possible using only 16-bit addresses. Programs containing more than 2¹⁶ bytes (64 kilobytes) of instructions and data therefore required special instructions to switch between their 64-kilobyte segments, increasing the complexity of programming 16-bit applications.

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, 16-bit integers, memory addresses, or other data units are those that are at most 16 bits (2 octets) wide. Also, 16-bit CPU and ALU architectures are those that are based on registers, address buses, or data buses of that size. 16-bit is also a term given to a generation of computers in which 16-bit processors are the norm.

See also

• Win32s
• 32-bit application

This article was originally based on material from the Free On-line Dictionary of Computing, which is licensed under the GFDL.