# MS-DOS v1.25, v2.0, v4.0 Source Code This repo contains the original source-code and compiled binaries for MS-DOS v1.25 and MS-DOS v2.0, plus the source-code for MS-DOS v4.00 jointly developed by IBM and Microsoft. The MS-DOS v1.25 and v2.0 files [were originally shared at the Computer History Museum on March 25th, 2014]( http://www.computerhistory.org/atchm/microsoft-ms-dos-early-source-code/) and are being (re)published in this repo to make them easier to find, reference-to in external writing and works, and to allow exploration and experimentation for those interested in early PC Operating Systems. # License All files within this repo are released under the [MIT License]( https://en.wikipedia.org/wiki/MIT_License) as per the [LICENSE file](https://github.com/Microsoft/MS-DOS/blob/main/LICENSE) stored in the root of this repo. # For historical reference The source files in this repo are for historical reference and will be kept static, so please **don’t send** Pull Requests suggesting any modifications to the source files, but feel free to fork this repo and experiment 😊. This project has adopted the [Microsoft Open Source Code of Conduct](https://opensource.microsoft.com/codeofconduct/). For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or contact [opencode@microsoft.com](mailto:opencode@microsoft.com) with any additional questions or comments. # Trademarks This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft trademarks or logos is subject to and must follow [Microsoft's Trademark & Brand Guidelines](https://www.microsoft.com/legal/intellectualproperty/trademarks/usage/general). Use of Microsoft trademarks or logos in modified versions of this project must not cause confusion or imply Microsoft sponsorship. Any use of third-party trademarks or logos are subject to those third-party's policies.