 For those who just joined or watching us, by the stream I will just do a quick bio description for those who are visually impaired. I am a white man, bald with beard, wearing a blazer, and we are in the seminar room full of nice people. Today we will talk about the commonly used free software licenses. If you had the opportunity to check my previous talk, I talked about what is a license, and the takeaway from that presentation is that the license is an authorization. License is what grants other people rights to reuse or to interact with a copyrighted work. With this presentation I would like to introduce you to the commonly used free software licenses. I will name some license and perhaps it's not the most loved one by you, and perhaps please don't be offended and say, oh you didn't mention my license. There's a lot of free software license out there in the wild. That's why I just said the commonly used. But if you wanted to introduce me to your very nice license, a full of free software features there, please, we can talk about that in a coffee. I'll be around until tomorrow. Right, so we'll talk and we do a quick recap about software license models, the type of free software licenses, and I will explain what are no reciprocal licenses, also called permissive licenses and reciprocal license that also very known as copy left. So basically, we went already today on this, but I would like to repeat myself, because this is important for this talk. When we are talking about license models, we have basically two. We have the proprietary one, which is the main purpose, is limited ways to assess and control source code, and we have the free and open source, which main purpose is free software freedom, and that we can have a classification on reciprocal license, also called copy left and non-reciprocal license called permissive. And please bear in mind that when you choose the term type of license, depending for an example, if it's reciprocal or non-reciprocal, or if you decide to go full proprietary, which here we don't suggest, but anyway, it will affect directly how the development of your software will be impacted, and also some software business models. So what is a free software license, basically from the legal perspective? We can understand that from policy perspective, from moral perspective, or even some philosophical perspective, but today, since we are in a legal track, I would like to point out some conceptions that are important for legal determination, for, you know, recognize when we say, okay, this is a free software license. And basically, there are two organizations that are curators of the term free software, what we can understand about free software, and another organization that is the creator of the term open source. The one is the free software foundation, not Europe, is based on US, and we are a sister organization. And the other one is the open source initiative, okay? And basically, the definitions that each one of the organizations come up with, there is a very rich historical development. But when we talk about legal aspects, I would consider the definition, you know, proposed by the free software foundation and the definition proposed by the open source initiative as synonyms, okay? And basically, I will stick with what the free software foundation has come with. Basically, when we are talking about free software, and when we are talking about licenses that can be considered a free software license, that license that, you know, provides basically to downstream users for types of freedoms, all right, the freedom to run the software for any purpose, to study the source code, and for that, it's really important to have access to source code. We have the freedom of distribution, redistribution of copies, and the less freedom is improvement of the software and redistribution of derivative works, okay? Yeah, the definition proposed by the OSI, although it's more verbose, basically, it conveys the same idea. Okay? And I, and which kind of classifications when we talk about when we now we are not talking more in the division about free software license and preparatory license. Now we are talking just about free software license. What kind of free software license can exist? And basically, we have two types. We have reciprocal and non reciprocal. And what are the principles that guide this main differentiation? When we are talking about reciprocal licenses, the main principle is if you distribute the software that you received, so someone is the copyright holder is has published her software under a reciprocal license, a couple of license, and now you are interacting with the software, you received the software. So yes, you can run the software for any purpose, you can use it. But now let's think that you wanted to redistribute the software, right? So if you distribute it, you must use the same license terms, right? And if you distribute the software, you must provide source code. So this is the principles of copy left is principle of reciprocal licenses. And when we are talking about no reciprocal license, usually also people call it permissive license, but I like the term non reciprocal. The main principle is if you read your distributor, the software code. So basically you're receiving software that is under no reciprocal license. If you redistribute it, you must provide license notice. And I will show you on a meter what a license note is. Well, examples of reciprocal license, we have several of them. And the most loved one, the GPL, the GNU public license. And we also have, for an example, the Mozilla public license. And since we are here in Europe, we have a license for public sector called European Union public license. But when we are talking about non reciprocal licenses, we have, for an example, the MIT license, BST, and the Apache 2 license. Okay. So let's start learning a little bit about the non reciprocal license, because the type of obligations that they convey there is a little bit more simple. So okay, so this is the MIT license. So nice to meet you. If you don't know MIT license, yeah. Okay. So yeah, and basically, this is a very simple license. This is the entire text of license. So and well, when we take the GNU public license, it's a little bit different, you know, and, and when we go to proper tire license, sometimes our contracts with, you know, yeah, full of paper there. But the MIT license is very simple. And basically, here we have the copyright grants. So permission is here by granted, free of charge to any person, you know, and all these legalese. But what I would like to point out is the license notice. So the notice obligation. Remember, when I was telling that, if you distribute, you must provide a license notice. So here is the notice obligation. They are both copyright notice and this permission notice shall be included in all copies of substantial portion of the software. Okay, so this is the type of obligation that you have under no reciprocal license. But when we are talking about copy left license, and that's the this board is too small for me to put in the entire code, the entire text of the license that I just wanted to put to point out to the rules and obligations of copy left license. So in here, what are the first rule? Remember, what when I mean by distribution or distribution. So imagine that you are a user of your company and or you are another developer, and you are you take receiving your downloading copy left code, no, and then you start using just for your personal use. So you don't need to do anything you can just use. All right. But the license obligations, the license terms will start to apply when you did redistribute this code. So on commercial or non commercial objectives doesn't matter. So once you upload your your work part with this copy left to work, you need to abide the license obligations. And the obligation is, if you distribute your code only in binary form, you know, and we are not talking about source code, for example, you compile your code, and now you're distributing it, you must make the corresponding source code source code available. So there is no way out. No pain or gain. So if you wanted to convey that, you needed to provide access to source code. Okay. But if you are distributing your code already in the source code form, well, congratulations, your job is done. Okay. And but there is another type of obligations when you consider about a copy left license. And basically is the principle called inbound equals outbound. So when you receive a copy left, a software that is protected by a copy left license, you need to keep the same license terms. You must re-license the software you received on the same copy left terms. So if GPL is entering, GPL is going out. If Mozilla public license is going, you need to keep the same license terms. Okay. Right. And perhaps you want to say, okay, but this is a little bit complex. How I choose a license for my software project? Well, there are some, you know, ways in order for you to choose your license. And we have even a portal called choose a license. We always recommend the GPL, the GNU public license, because well, it's a consolidated license. It's a license that has a story, has a reputation. And you know, it's copy left license. So it, the main objective to license is to safeguard software freedom. Right. But usually you need, there is some, yeah, you know, depending on objectives, there are other types of license that perhaps it's useful for you. Okay. So I just wanted to show again, don't be offended if your license is not there. But basically these are the most common, you know, free software license. So we have the GPL that also is considered one license that are considered strong copy left license. We have the A GPL for network copy left. We have the LGPL for libraries called also weak copy left and Mozilla public license. And also when we are talking about no reciprocal, we have the MIT, the Apache, and other types of licenses. All information about licenses easily findable, you know, in the internet, you can read more about this type of license. And if you are searching for a license, yeah, you can, you can certainly find information on how license can suit for your project. In this note, I finished my presentation. Once again, I thank you very much for your attention.