Open-Source Licences

From Wikipedia:

Open source is source code that is made freely available for possible modification and redistribution. [...] Open source promotes universal access via an open-source or free license to a product's design or blueprint, and universal redistribution of that design or blueprint.

Licences I would want to use

When choosing an open-source licence, I tend to use the following criteria:

  1. Licence is approved by major FOSS communities:

    • FSF

    • OSI

    • Debian

    • Fedora

  2. Licence text is easily retrievable from SPDX

  3. (preferably) Licence is compatible with GPLv3

  4. Licence is relatively formal

    • That is, I try to avoid licences like WTFPL or Beerware. In case of a legal trouble, it may be problematic to try to appeal using it.

Codeberg has an excellent licence decision diagram.


My current go-to licence is the ISC License: It's equivalent to my other favourite, the BSD 2-Clause "Simplified" License (as well as the MIT License), while being even shorter and more descriptive (due to some unnecessary text being removed).


ISC License (sometimes also known as the OpenBSD License) is a permissive software licence. It allows usage, modification, and distribution while requiring attribution (through inclusion of copyright notice and permission notice).

Applicable licences

Licences, that meet all the criteria, are:

"Licence" vs. "License"

When writing or coding, I use British English for spelling. However, all the aforementioned licences either originated in the USA or use American spelling. The licences' texts should be copied verbatim, so when applying a licence one should use the American spelling. Thus, I use the word "license" when it's found the name or the text of the licence in question.

Wrong: I use the MIT Licence
Correct: As for the licence, I use the MIT/Expat License.
NB! The verb is still spelled "to license"

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