What is free and open source software (FOSS)?

Posted by Greten on 25 Apr 2013 under Terms

In its most common or "layman" definition, free and open source software or FOSS is a blanket term referring to those programs and digital media that are distributed under any of the several different licenses with the intention of keeping it free.

The term "layman" here is a bit stretch because the majority of people and businesses are using the non-free or proprietary software such as those developed by Microsoft, Apple, Adobe and their other friends in Business Software Alliance. You know? Those guys who will just show-up on the door of your office demanding that they inspect your computers? There's a bigger probability that CEO Joe knows Adobe Photoshop but not GIMP, and that Janitor Bob is using Excel to make a checklist on which restrooms were already cleaned instead of LibreOffice Calc.

Here at iTitser, my advocacy is to convince schools, colleges and other educational institutions to embrace the use of free and open source software programs in their computer laboratories and other school requirements that require the use of computer. I use the phrase "free and open source software" in several other articles and will continue to use it. Thus, I need to define and explain was FOSS is all about.

Two phrases, different meaning

As I mentioned earlier, FOSS is a blanket term. There are actually two groups of software here: free software and open source software.

While I was reading about FOSS around three to four years ago (did not document them, I was not anticipating that I will write this essay back then), my first impression what like this. Free software is just... well free software. You can get them for free. The author or programmer may ask for donation or something but otherwise, you do not need to shell-out money to use it. You are also free to copy and distribute it. However, the restrictions on whether you can modify it or not and up to what extent may vary from software to software.

foss-iconThe term "open source", on the other hand, is derived from the fact that the executable program comes with the source code, and you can use this source code to modify the program in some ways to suit your needs. The non-free software do not come with source code and includes a provision in which you are not allowed to reverse engineer it. All open source software are free. Otherwise, what's the point of having a non-free software business model if the source code is there, an open invitation for reverse engineering. Also, all proprietary software comes only with binary or executable program and no source codes.

These are my assumptions based on practical business model that will work; if you know of any exception e.g., an open-source but proprietary software please let me know. I'm kind of curious how there business model works.

To summarize, my impression is that free software are more restrictive than open source. All open source software are free, but not all free software are open source. Then, as I continue to expand my research, I realized that the people who invented the phrases "free software" and "open source software" have definitions different from what I first thought. There's some sort of activism involved here.

Free Software Movement vs Open Source Movement

As it turns-out, the phrases "free software" and "open source software" were actually created by two factions that either created or supported the creation of various free and open source software programs that we use today. It's probably the reason why the umbrella term "free and open source" was created, to give nod to both of these factions.

Free Software Movement

The first faction is the Free Software Movement led by Free Software Foundation. This is the group behind the development of GNU Operating System, from which Linux was derived, and Linux in turn spawned Red Hat, Ubuntu, Kahel, among others. The ethos of the Free Software Movement is to make all software free while staying within the boundaries of copyright laws. One way to accomplish this is by producing free software programs such as the aforementioned GNU to snatch market share from the proprietary software.

The Free Software Movement is very particular with their definition of "free". Free here does not mean you can get it without paying. Free here means you can do the following:

  • free to use - well yes, use it without worry that those BSA guys will knock on your door and confiscate your computers.
  • free to copy and distribute - install it in your computer, in several computers used in your business, in your friends' and family members' computers, etc., you are limited only by time, electric bill and the owner's permission if you are not the owner.
  • free to modify - the Free Software Movement always require the source code to be included so that others can study it, modify it and create their own version; this is allowed provided the modified version is also released with the same conditions (i.e., free to use, copy and modify).

This is the freedom that the Free Software Movement is trying to protect. The term "free software" is all about this freedom. Their favorite analogy is "free speech, not free beer". In fact, you are actually allowed to make some money out of free software programs. You can burn CDs and sell them, or you can offer computer services in which you will install GNU or Linux operating systems in your client's computer. However, in doing so you should assure the three aforementioned freedoms: the computer owner can use it without any restrictions; if you sell them one CD and they have 10 computers, they should be free to install it on 10 computers; and the source code should be included in your CD or your installations so they can modify it to suit their needs.

To ensure the three aforementioned freedoms, the Free Software Movement requires that the software released as free software, especially those that were derived from what they developed, to use the GNU GPL license. I would no longer go into details of what GNU GPL license states, you can read it here. According to Free Software Movement, the GNU GPL license, unlike the license of proprietary software, is enforced to ensure your freedom: to use, to copy and distribute, and to modify. Software programs released under GNU GPL license are required to either have the source code included with them, or have instructions on how to easily obtain them without paying e.g., by providing a website from where the source code can be downloaded.

Open Source Movement

The second faction, the Open Source Movement is actually an off-shoot of Free Software Movement initially conceived as "marketing arm" through which big companies and other powerful stakeholders can be obtained as supporters and users of free software. The phrase "open source" was actually conceived as some sort of office jargon or managerese because the bosses of big companies might think "free software means no money, so why support it?"

The two factions gradually split even though they still see each other as allies and collaborate on certain projects. It's just important to them that they are cited and credited as separate groups and not confuse one for the other e.g., do not say that GNU is open source because it's from Free Software Movement, not from Open Source Movement.

Some people from Open Source Movement might see those in the Free Software Movement as very much fixated with their concept of freedom, while some people from Free Software Movement might see those from the Open Source Movement as willing to sacrifice their principles to accomplish certain objectives, e.g., more efficient software. This is how I see the conflict between these factions but I am saying that either or both of them are evil, just different kind of good guys.

If the Free Software Movement has Free Software Foundation, the Open Source Movement has the Open Source Initiative, a non-profit corporation that approves the licenses that software released as open source may use. Unlike Free Software Movement, the Open Source Movement does not issue specific licenses. Instead, the Open Source Movement has list of approved licenses include the GNU GPL of Free Software Movement.

One of the known contributions of Open Source Movement are the OpenOffice suite and its derivative LibreOffice. OpenOffice was actually started by Sun Microsystems, who decided to release the code of StarOffice suite as open source and invited the open source community to further develop it. When Sun was acquired by Oracle, they could not get along with the open source community and thus, the community forked OpenOffice into LibreOffice. This is where the savviness of Open Source Movement in dealing with big corporations really manifest. First, they have the full backing support of a corporation. Then, when things are not going as planned, they know the license very well and what they can and cannot do e.g., they can use the codes but they cannot use the brandname. Thus, they forked LibreOffice.

The factions controlling the OpenOffice and LibreOffice thus split, but still within the bounds of Open Source Movement. Both factions also have corporate backers. [Click here to know more about the story of OpenOffice and LibreOffice].

One thing that my impression is contrary to how these two factions defined themselves is this: I said in the earlier section that free software is just any software that you can get without shelling-out money, while open source software is a software that is free and always include the source code. As it turns-out, the Free Software Movement always require the inclusion of source code in using their GNU GPL license and thus we can expect that all free software, as per Free Software Movement's definition, will include source code (except for non-program software like image and media files perhaps). The Open Source Initiative, on the other hand, support several licenses including those that may not require the release of source code. Thus, the programs supported by Open Source Movement may include those that are not really open-source.

On issue of DRM

If there is one issue that highlights the divergent philosophies of Free Software Movement and Open Source Movement, it is the issue of digital rights management or DRM.

To give you an idea of what a DRM is, it's a technology... a piece of code or a part of the device that limits what you can do with a digital product that you bought. For example, copies of music bought from iTunes can only be played using iPod and other devices developed by Apple.

The Free Software Movement is opposed to any form of DRM. They believe that when you bought something and it's already in your device, the vendor should no longer have control over it. One particular ugly example they cited is when Amazon remotely deleted the digital copy of the novel 1984 that was already bought by customers and stored in their Kindle devices. Amazon cited that it is not the version that they acquired the rights to sell, and compensated their customers for their lost. For Free Software Movement, however, vendors like Amazon should not have any control on what was already transmitted to your device. Your device is yours alone and whatever they want to do with it, they should have your permission. How subtle? The novel deleted is 1984 and devices like iPod and Kindle are being used like telescreens? Big brother must be watching us.

I kind of agree with this stance of Free Software Movement. They even have a mocking term for it. DRM should be digital restriction management, not digital rights management. Isn't when you say "right", it is something fundamental, something that belongs to you by virtue of being a human person? These big companies have no business "managing" our rights.

The Open Source Movement, on the other hand, is more concerned about the economic impact of DRM. They do not intend to stop DRM itself, just stop its use to create monopolistic situation. Hence, the Open Source Movement would like to create a system of "open source DRM", a DRM system being managed by a non-profit organization and not by vendors. This was originally envisioned by one of their major supporters, the Sun Microsystems, with its DReaM project. In theory, it should allow music purchased from iTunes to be played in devices other than those manufactured by Apple, provided that the non-profit organization approved the device. I'm not sure what happened to it now that Sun Microsystems is already defunct. Did Oracle, the company that acquired Sun, continued it?


The Free Software Movement and the Open Source Movement created the phrases "free software" and "open source software" respectively. They might have different ethos and different advocacies. For most computer users however, there's just the umbrella term FOSS: software that can be used without hassle, software than can be copied several times, whatever other limitation is there is on the basis of individual licenses.

To be honest, I find it difficult tracking down which group is responsible to which software so please don't beat me up if you're from either Free Software Movement or Open Source Movement and I misrepresented you in some parts of my writing. I did my research but I'm open for corrections; just provide me references to support your claims.


Last updated on 09 Dec 2018.

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