MIT License

Noun · Open Source · Origin: 1988

Definitions

MIT License is one of the most popular and permissive open-source software licenses, originating from the Massachusetts Institute of Technology. It allows anyone to use, copy, modify, merge, publish, distribute, sublicense, and sell copies of the licensed software with virtually no restrictions, as long as the original copyright notice and license text are included in all copies or substantial portions of the software. The license explicitly disclaims all warranties, providing the software as-is. Its brevity (just a few paragraphs) and simplicity make it one of the easiest licenses to understand and comply with. The MIT License is compatible with most other licenses, including the GPL, making it a safe choice for libraries and tools that might be used in diverse projects. Major projects using the MIT License include jQuery, Node.js, Ruby on Rails, and React. Its permissiveness means that proprietary software can incorporate MIT-licensed code, which some free software advocates see as a weakness compared to copyleft licenses.
In plain English: The simplest open-source license: use the code however you want, even in commercial products, just keep the copyright notice. That's it.

1988: The MIT License originates at the Massachusetts Institute of Technology as a permissive free software license
2000s: Its extreme brevity (about 170 words) and permissiveness make it the most popular open-source license on GitHub
2015: GitHub adds a license picker that defaults to suggesting MIT, further cementing its dominance for new projects