1. OPEN SOURCE SOFTWARE LICENSES
{{ for humans }}
Shijie Feng Hack13right 2-12-
2016

2. WHAT IS
Computer Program: source code
Development Model: peer production
Value System: freedom + community

3. FREE SOFTWARE MOVEMENT
Richard Stallman
GNU Project
GPL License
Free Software
Foundation
Linus Torvalds
Linux Kernel (kernel for
GNU, Android,
Chrome)
Released under GPLv2

4. "Linus Torvalds’s style of development – release early and often,
delegate everything you can, be open to the point of promiscuity
– came as a surprise. No quiet, reverent cathedral-building here
– rather, the Linux community seemed to resemble a great
babbling bazaar of differing agendas and approaches (aptly
symbolized by the Linux archive sites, who’d take submissions
from anyone) out of which a coherent and stable system could
seemingly emerge only by a succession of miracles."
-- Eric Raymond, The Cathedral and the Bazaar

5. FREE SOFTWARE v. OPEN SOURCE
4 Freedoms
freedom to run software, to study and
change it, and to redistribute copies
with or without changes
Free speech, not free beer
Rebranding
1998: adopted name “open source” at a
strategy session in Palo Alto, after
Netscape announced its release of
source code

6. Types of Open Source Licenses
Permissive
It lets people do anything they
want with your code as long as
they provide attribution back to
you and don’t hold you liable.
eg. Python, jQuery, Rails, Swift,
and Android
Strongly Protective
It requires anyone who
distributes your code or a
derivative work to make the
source available under the same
terms.
eg. WordPress, Linux, Bash
Weakly Protective
It allows integration into
proprietary software without
being required to release the
source code of their own
components.

7. Permissive Licenses
{{ I’m friends with everyone <3 }}

8. Permissive License
MIT License (most popular)

9. Permissive License
MIT License (most popular)
“Do whatever you want! Just don’t sue me.”
BSD 3-Clause License

10. BSD 3-Clause License Example:

11. Permissive License
MIT License (most popular)
“Do whatever you want! Just don’t sue me.”
BSD 3-Clause License
MIT + “Don’t use my name in promotion without asking me.”

12. Permissive License
MIT License (most popular)
“Do whatever you want! Just don’t sue me.”
BSD 3-Clause License
MIT + “Don’t use my name in promotion without asking me.”
Apache 2.0

13. Apache 2.0 Patent Clause:

14. Permissive License
MIT License (most popular)
“Do whatever you want! Just don’t sue me.”
BSD 3-Clause License
MIT + “Don’t use my name in promotion without asking me.”
Apache 2.0
“I hereby grant you the patent rights.”

15. Strongly Protective Licenses
{{ I love you as long as you’re not selfish }}

16. Strongly Protective License
GPLv2, GPLv3

17. GPLv2 Excerpt:

18. Strongly Protective
GPLv2, GPLv3
share and share alike
Copyleft
Copyleft is a method for making a program free software and requiring all
modified and extended versions of the program to be free software as well.
Impose redistribution requirements on downstream versions

19. WHY COPYLEFT?
“[I]nstead of putting GNU software in the
public domain, we ‘copyleft’ it. Copyleft
says that anyone who redistributes the
software, with or without changes, must
pass along the freedom to further copy
and change it. Copyleft guarantees that
every user has freedom.”

20. Questions?
=^.^=
Resources:
-Open Source Initiative
-GNU.org Licenses
-Ask your friendly lawyer =]