| Abkürzung | Bereich | Staat | Bedeutung |
| M | Physik | Drehmoment | |
| m | Einheit | Meter | |
| Physik | Masse | ||
| m.a.W. | Allgemein | mit anderen Worten | |
| MAD | Geheimdienst | D | Militärischer Abschirmdienst |
| MAP | Computer | Memory Allocation Map | |
| MASM | Software | Macro Assembler | |
| MAU | Computer | Media Access Unit | |
| MB | Einheit | Megabyte | |
| Computer | Middle Button | ||
| MBASIC | Software | Microsoft BASIC (Programmiersprache) | |
| MBPS | Computer | Megabytes per Second (Millionen Instruktionen pro Sekunde) | |
| MBR | Computer | Master Boot Record | |
| MBX | Computer | Mailbox | |
| MC | Technik | Music Casette | |
| Computer | Machine Code | ||
| MCA | Computer | Micro Channel Architecture | |
| MCB | Computer | Memory Control Block | |
| MCGA | Computer | Multicolor Graphics Array | |
| MCI | Computer | Media Control Interface | |
| MCU | Computer | Micro Control Unit | |
| MD | Computer | Make Directory | |
| Monochrome Display | |||
| MDA | Computer | Monochrome Display Adapter | |
| MDI | Computer | Multiple Document Interface | |
| MDK | Computer | Multimedia Developers Kit | |
| MEB | Computer | Memory Expansion Board | |
| MFC | Software | Microsoft Foundation Classes | |
| MFLOPS | Computer | Million Floating Point Operations per Second | |
| MGA | Computer | Monochrome Graphics Adapter | |
| MIDI | Technik | Musical Instrument Digital Interface | |
| MIPS | Computer | Millions of Instructions per Second (Millionen Instruktionen pro Sekunde) | |
| MISC | Allgemein | GB | Miscellaneous (Verschiedenes) |
| MIT | Institut | GB | Massachusetts Institute of Technology |
| Mitarb. | Allgemein | D | Mitarbeiter |
| MKDIR | Computer | Make Directory | |
| ML | Computer | Machine Language | |
| MM | Computer | Multimedia | |
| Haus | D | Monatsmiete | |
| Mm | Einheit | Megameter | |
| mm | Einheit | Millimeter | |
| MMU | Computer | Memory Management Unit | |
| MO | Computer | Magneto-Optical | |
| möbl. | Haus | D | möbliert |
| MOD | Mathematik | Modulus | |
| Computer | Modem | ||
| Modem | Computer | Modulator / Demodulator | |
| mögl. | Allgemein | D | möglich |
| MOV | Computer | Move | |
| MOVS | Computer | Move String | |
| MPE | Software | Multi Processing Environment (Betriebssystem) | |
| MPEG | Institut | USA | Moving-Pictures-Experts-Group |
| MPG | Software | MPEG-File | |
| MPU | Computer | Microprocessor Unit | |
| MR | Computer | Modem Ready | |
| MS | Computer | Memory System | |
| Firma | USA | Microsoft Corporation | |
| Ms | Einheit | Microsekunde | |
| ms | Einheit | Millisekunde | |
| MS-DOS | Software | Microsoft Disk Operating System (Betriebssystem) | |
| MSAV | Software | Microsoft Anti Virus | |
| MSC | Software | Microsoft C (Programmiersprache) | |
| MSCDEX | Software | Microsoft CD Extensions | |
| MSD | Computer | Mass Storage Device | |
| MSDN | Software | Microsoft Developer Network | |
| MSG | Software | Message | |
| MTA | Computer | Multiple Terminal Access | |
| MUL | Mathematik | Multipy | |
| MV | Computer | Move | |
| MVDM | Computer | Multiple Virtual Dos Machines | |
| MVGA | Computer | Monochrome Video Graphics Array | |
| MVS | Software | Multiple Virtual Storage (Betriebssystem) |