MS-DOS

MS-DOS is a command-line operating system for IBM PC-compatible computers, developed by Microsoft and first released in 1981. It uses a command interpreter and a file system built around drives, directories, and files.

COMMAND.COM: COMMAND.COM is the MS-DOS command interpreter and the program that provides its command prompt. It reads commands, runs built-in operations, and launches other programs.
86-DOS: 86-DOS was a 1980 operating system for Intel 8086-based computers, created by Seattle Computer Products. Microsoft acquired rights to this system and developed it into MS-DOS.
DOS applications: DOS applications are programs designed to run under DOS, often using direct hardware access and command-line options. They depended on DOS conventions for launching, files, and access to PC resources.
IBM PC compatible: An IBM PC-compatible computer is a personal computer designed to run software and hardware made for the IBM PC architecture. DOS helped make a shared software platform possible across competing manufacturers.
FAT file system: The FAT file system organizes files using allocation tables that track which disk clusters belong to each file. MS-DOS used FAT to store and locate files on disks.
Seattle Computer Products: Seattle Computer Products was a hardware company that made Intel 8086-based computers and created 86-DOS. Its operating system became the starting point for MS-DOS.
PC boot process: The PC boot process is the sequence that initializes hardware and loads an operating system after power-on. DOS was commonly loaded from a disk during this startup sequence.
PC clone: A PC clone is a computer compatible with the IBM Personal Computer but produced by another manufacturer. Clones spread DOS beyond IBM's own machines.
CONFIG.SYS: CONFIG.SYS is a text configuration file used by DOS to set system options and load device drivers during startup. It shaped the memory and devices available after an MS-DOS boot.
IBM Personal Computer: The IBM Personal Computer is IBM's 1981 personal computer, built around an Intel 8088 processor and an open architecture. IBM selected Microsoft's DOS for the original PC.

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