# microsoft/MS-DOS

The original sources of MS-DOS 1.25, 2.0, and 4.0 for reference purposes

Repository: https://github.com/microsoft/MS-DOS
Canonical: https://ross.abutalabs.com/products/ms-dos
Homepage: https://en.wikipedia.org/wiki/MS-DOS
Language: Assembly
License: MIT
License Family: permissive
Topics: ms-dos
Archived: true
Last push: 2024-04-25T22:32:47+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 2991, "days_push": 860, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 32280, forks 4671 (observed 2026-08-28T04:11:57.491877+00:00)

## What it is
The original source code of MS-DOS versions 1.25, 2.0, and 4.0, published by Microsoft under the MIT license for historical reference. It is a static archive meant for exploration and study of early PC operating systems, not for active development.

## Use cases
- study the source code of an early PC operating system
- explore how MS-DOS was implemented in assembly
- reference historical operating system code for research or writing
- learn how DOS file systems and command interpreter worked
- experiment with vintage operating system source code

## When to choose
- you want authentic, original MS-DOS source code for study or reference
- you are researching the history of PC operating systems
- you want to fork and experiment with early DOS internals

## When to avoid
- you need a usable modern DOS or command-line environment (use FreeDOS instead)
- you expect an actively maintained or extensible project
- you want to contribute changes upstream (the repo is explicitly static)

## Facets
- artifact type: learning-resource
- maturity: maintenance
- function: interpreter, file-system, developer-tools
- domain: operating-systems, programming-languages, documentation
- platform: cpp, c, cross-platform
- tags: ms-dos, historical-source-code, assembly, operating-system, reference, retrocomputing

## Member repositories
- microsoft/MS-DOS (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:57.491877+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:52:07.571476+00:00, confidence not recorded.
  - readme: https://github.com/microsoft/MS-DOS (fetched 2026-08-28T04:11:57.491877+00:00, sha d99f96705078)
  - homepage: https://en.wikipedia.org/wiki/MS-DOS (fetched 2026-08-29T07:49:03.021814+00:00, sha de7e6d819f73)
  - site_page: https://en.wikipedia.org/wiki/Wikipedia:About (fetched 2026-08-29T07:49:03.029525+00:00, sha 23a807abd0b6)
  - site_page: https://en.wikipedia.org/wiki/Installable_File_System (fetched 2026-08-29T07:49:03.032992+00:00, sha 065f9ee62905)
  - site_page: https://en.wikipedia.org/wiki/File:MS-DOS_6.2_Update_Install_Floppy_Discs_(German).jpg (fetched 2026-08-29T07:49:03.035681+00:00, sha cf07e350bbe7)
- Data as of 2026-08-30T08:39:29.467469+00:00.