[dragonwriter]

Free Software and Open Source have definitions that are both on their face and in practical application by the bodies responsible for each almost entirely identical. Neither is a subset of the other.

If you are concerned about mandating users provide modifications by a similar license to the one they received material under, what you want is copyleft.

[adastra22]

“Free software” means copyleft. The free software foundation manages copyleft licenses. The term open source was explicitly coined to differentiate from the more restrictive free software / copyleft.

All free software licenses are open source licenses. Not all open source licenses are free software licenses.

[dragonwriter]

> “Free software” means copyleft.

No, it doesn't. The FSF uses “Free Software” to refer to a broad class that is essentially identical to the OSI use of “Open Source.”

The term the FSF uses for copyleft is “copyleft”, which is a subset of Free Software.

[cxr]

To underscore the point here: the FSF

1) hasn't/doesn't publish a free software definition that describes copyleft as a precondition to free software

2) hasn't/doesn't claim in any of their non-normative commentary that the definition has that precondition

3) readily and regularly refers to projects published under permissive licenses like the BSD, MIT/X11, and Apache licenses as "free software", despite not being copyleft licenses

4) themselves publish/maintain/govern software projects that are licensed under permissive licenses like the aforementioned non-copyleft licenses

The claim that "'free software' means 'copyleft'" is a pernicious, bizarrely recurring but wildly misinformed claim that only shows up on message boards by people who can't ever have actually read primary sources that explain the positions of the organization they purport to describe, and have instead just, like, decided they understand the topic (through, I dunno, osmosis or something, I guess).

[adastra22]

https://www.gnu.org/philosophy/free-sw.html

Linked to from here:

https://www.fsf.org/about/what-is-free-software

Very explicit about open source being different from free software.

Also if what you say is true, there would be no reason for “open source” to exist. It was coined by Christine Peterson explicitly because the term free software conveyed a different ideal than the BSD/MIT license crowd was aiming for.

[umanwizard]

> nearly all open source programs are in fact free.

You are just wrong, and your first link proves it. The definitions are essentially identical. The philosophies behind them are different.

It's like the "Gulf of America" vs. the "Gulf of Mexico". You are talking about the same territory in either case, just expressing a different viewpoint about it.

[pxc]

This is completely false and ahistorical. The first license associated with the term "open-source" was the MPL, which is a copyleft license.

Open-source never attempted to distinguish itself from free software in terms of licensing or content, and "free software" has always included permissive licenses.

You can find lots of free software licenses which are not copyleft listed on the FSF website, with links to longer commentaries on them. The FSF clearly identifies them as free software licenses, and always has.

https://www.gnu.org/licenses/license-list.html

this page is linked to from FSF.org here:

https://www.fsf.org/licensing/

Take a few minutes reading the publications of the organizations and movements you're misrepresenting. Take a look at the OSI's Open-Source definition as well.

[andrewshadura]

This statement is incorrect.

[bigstrat2003]

Indeed it is, but can people please not abuse the flag function for such cases? It's not against the rules to be mistaken, and "flag" is not supposed to be a super downvote.

[andrewshadura]

I never use the flag function.

[jibal]

You are correct ... the other responses to you are not. "Free software" as in the FSF is "free as in freedom, not free as in free beer", which is why copyleft was invented, to establish such a distinction.

[tsimionescu]

No, this is completely wrong. Free/libre software is distinguished from "gratis" software, such as demos or shareware. Any software that is freely available for users to legally modify and redistribute however they see fit, under the same license or some other, is free software.

Examples of non-free software are shareware like WinRar, software only available for non-commercial use like OMNeT++ [0], and (slightly more controversially) things like ElasticSearch or MongoDB.

[0] https://omnetpp.org/intro/license

[jibal]

It's not completely wrong ... how rude. Shareware isn't even open source, generally, and it certainly isn't gratis--you have to pay for it, or at least should, and there are often restrictions or time limits if you don't. Again, the "free" in "free software" refers to freedom, not free beer.

https://www.gnu.org/philosophy/free-sw.html

> “Free software” means software that respects users' freedom and community. Roughly, it means that the users have the freedom to run, copy, distribute, study, change and improve the software. Thus, “free software” is a matter of liberty, not price. To understand the concept, you should think of “free” as in “free speech,” not as in “free beer.” We sometimes call it “libre software,” borrowing the French or Spanish word for “free” as in freedom, to show we do not mean the software is gratis.

And

> “Open source” is something different: it has a very different philosophy based on different values. Its practical definition is different too, but nearly all open source programs are in fact free. We explain the difference in Why “Open Source” misses the point of Free Software.

etc.

[tsimionescu]

That definition, and Richard Stallman himself, completely agree with me. A BSD license also guarantees "that the users have the freedom to run, copy, distribute, study, change and improve the software".

Here is Stallman spelling it out explicitly:

https://www.gnu.org/licenses/bsd.en.html

> The two major categories of free software license are copyleft and non-copyleft. Copyleft licenses such as the GNU GPL insist that modified versions of the program must be free software as well. Non-copyleft licenses do not insist on this. We recommend copyleft, because it protects freedom for all users, but non-copylefted software can still be free software, and useful to the free software community.

> There are many variants of simple non-copyleft free software licenses, such as the Expat license, FreeBSD license, X10 license, the X11 license, and the two BSD (Berkeley Software Distribution) licenses.

So, I stand by my assertion. You are completely wrong in saying that only copy left licenses are free/libre software, even according to Richard Stallman himself.

[pabs3]

The BSD license does not offer the same software freedom guarantees as copyleft licenses though, since downstreams can elect to not release the source code. You are right otherwise though.

[F3nd0]

> Shareware isn't even open source, generally, and it certainly isn't gratis--you have to pay for it, or at least should, and there are often restrictions or time limits if you don't. Again, the "free" in "free software" refers to freedom, not free beer.

Yes. The comment you are replying to already said this: ‘Free/libre software is distinguished from "gratis" software’.

Your earlier comment wasn’t wrong for saying that ‘free software’ refers to freedom; that part was correct. But it was wrong for agreeing with a comment which claimed that ‘free software’ means ‘copyleft’. Copyleft is free software, but free software isn’t always copyleft.

Saying that ‘free software means copyleft’ is like saying that ‘bird means goose’. Goose is a kind of bird, but not every bird is a goose; just like copyleft licences are free, but not every free licence is copyleft. The responses (which you called incorrect) were trying to explain this important difference.

[jakelazaroff]

Copyleft licenses don't even need to be free! All copyleft means is that derivative works must use the same license. For example, the Creative Commons BY-NC-SA license [1] wouldn't fulfill freedom 0, since you can't use the material for commercial purposes.

(Granted, Creative Commons licenses are typically not used for software, but the point stands.)

[1] https://creativecommons.org/licenses/by-nc-sa/4.0/