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The design implements a [[32-bit computing|32-bit]] [[instruction set]], with 32-bit registers and a 16-bit internal [[System bus|data bus]].<ref name="Starnes" /> The [[address bus]] is 24 bits and does not use [[memory segmentation]], which made it easier to program for. Internally, it uses a [[16-bit computing|16-bit]] data [[arithmetic logic unit]] (ALU) and two more 16-bit ALUs used mostly for addresses,<ref name="Starnes">{{cite magazine |last=Starnes |first=Thomas W. |date=April 1983 |url=http://www.easy68k.com/paulrsm/doc/dpbm68k1.htm |title=Design Philosophy Behind Motorola's MC68000 |magazine=[[Byte (magazine)|Byte]] |volume=8 |issue=4 |access-date=2018-06-19 |archive-date=July 24, 2018 |archive-url=https://web.archive.org/web/20180724041918/http://www.easy68k.com/paulrsm/doc/dpbm68k1.htm |url-status=live }}</ref> and has a 16-bit external [[memory bus|data bus]].<ref>{{cite book |author=<!-- Unstated --> |year=1992 |location=Phoenix, Arizona |title=Motorola M68000 Family Programmer's Reference Manual |url=http://www.freescale.com/files/archives/doc/ref_manual/M68000PRM.pdf |publisher=[[Motorola]] |at=p. 1-1 |isbn=0-13-723289-6 |access-date=August 12, 2005 |archive-date=September 24, 2015 |archive-url=https://web.archive.org/web/20150924015505/http://www.freescale.com/files/archives/doc/ref_manual/M68000PRM.pdf |url-status=live }}</ref> For this reason, Motorola termed it a 16/32-bit processor.
As one of the first widely available processors with a 32-bit instruction set, and running at relatively high speeds for the era, the 68k was a popular design through the 1980s. It was widely used in a new generation of [[personal computer]]s with [[graphical user interface]]s, including the [[Macintosh]], [[Amiga]], [[Atari ST]], and [[X68000]]. The 1988 [[Sega Genesis|Sega Genesis/Mega Drive]] console is also powered by a 68000.
The 68000 was followed by additional processors implementing full 32-bit ALUs as part of the growing [[Motorola 68000 series]]. The original 68k is generally software [[Forward compatibility|forward-compatible]] with the rest of the line despite being limited to a 16-bit wide external bus.<ref name="Starnes" />
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