Software Licences Explained#

Licenses are responses to historical pressures, not abstract ideologies. 👉 It’s basically choosing a social contract, not a legal detail.

TLDR#

MIT → Freedom without obligations
Apache 2.0 → Freedom with legal safety
GPL → Freedom with reciprocity

Licence summary#

License	Birthdate	Creator / Origin	Mental model	Commercial use?	Closed-source allowed?	What must be shared	Famous examples	Who profits
Unlicense	~2010	Public domain attempt	Do literally anything.	✅ Yes	✅ Yes	Nothing	—	Anyone
MIT	1988	MIT (academia)	Take it and run.	✅ Yes	✅ Yes	Keep license notice	NumPy, Flask, Requests	Everyone
BSD (2/3-Clause)	1988	UC Berkeley	Open code, no strings.	✅ Yes	✅ Yes	Keep copyright notice	FreeBSD, OpenSSH	Apple, Juniper
Apache 2.0	2004	Apache Software Foundation	Open, but legally safe.	✅ Yes	✅ Yes	Preserve notices + patent peace	Kubernetes, Spark, Kafka	Google, Confluent
MPL 2.0	1998	Netscape / Mozilla	Open files, closed products.	✅ Yes	⚠️ Except MPL files	Modified MPL files	Firefox	Mozilla
LGPL	1991	Free Software Foundation	Share the core, not the app.	✅ Yes	⚠️ App yes, library no	Changes to LGPL library	glibc, FFmpeg	Red Hat, IBM
GPL (v2/v3)	1989 (v1)	Richard Stallman (FSF)	Take it, but give back.	✅ Yes	❌ No (if distributed)	Full source + same license	Linux kernel, WordPress, Git	Automattic, Red Hat, Canonical, GitLab
AGPL	2007	FSF + Affero Inc.	SaaS must share too.	✅ Yes	❌ No (incl. SaaS)	Source, incl. network use	Nextcloud, Mastodon	Nextcloud GmbH
Proprietary	—	Vendor-defined	You rent, not share.	⚠️ Limited	✅ Yes	Fees, data, compliance	Windows, macOS	Microsoft, Apple

How do companies monetize open source?#

Most organizations and individuals make money with open-source software through:

Hosting, support, subscriptions, enterprise services, and trademarks (GPL, AGPL, LGPL)
Cloud services and managed platforms (Apache 2.0, BSD, MIT)
Support, dual licensing, enterprise contracts (LGPL)
Products, hardware, internal use (BSD)
Licenses, subscriptions, lock-in (Proprietary)

The monetization model is often similar across licenses, focusing on added value, services, or proprietary extensions rather than direct software sales.

How to choose a license?#

Ask yourself one simple question first:

❓ Am I okay with someone taking my code, improving it, and never contributing back?

Yes → choose MIT
Maximum adoption, zero friction. Your code can go anywhere.
Yes, but I want legal & patent safety → choose Apache 2.0
Same freedom as MIT, with stronger protections for companies.
No → choose GPL
You allow commercial use, but improvements must stay open.

There is no “best” license — only a license that matches your values and goals.

License philosophy and intent#

License	Philosophy	Intent
GPL (v2/v3)	Strong copyleft / reciprocity	Ensure that all distributed modifications remain open-source under the same license, protecting user freedoms and preventing private capture of community code.
Apache 2.0	Permissive with legal safety	Promote broad collaboration and commercial adoption while providing explicit patent protections and requiring preservation of notices.
MIT	Ultra-permissive	Maximize reuse and adoption by imposing minimal restrictions, allowing selling, re-licensing, and closed-source derivatives.
LGPL	Weak copyleft (library-focused)	Allow proprietary applications to link against open libraries while ensuring improvements to the library itself remain open.
AGPL	Network copyleft	Close the SaaS loophole by requiring source code disclosure to users who interact with the software over a network.
BSD (2/3-Clause)	Permissive and business-friendly	Enable nearly unrestricted use, including proprietary and commercial use, as long as copyright notices are retained.
MPL 2.0	File-level copyleft	Require sharing of modified MPL-licensed files while allowing combination with proprietary code in larger systems.
Unlicense / Public Domain	No philosophy enforced	Remove all restrictions entirely, placing the code effectively in the public domain for unrestricted reuse.