 You guys hear me okay? Yeah, that's great. Okay, so let's talk about GPL. So as Daniel already said, most people have already probably heard that WordPress is GPL. Great. So GPL version 2 is specific really. So what does that mean? What does that really mean? It's an open source licence, right? So anybody can just go and have a look up for example make.wordpress.org and go and read the source code. In the source code there's a licence.txt file which actually contains the whole of GPL. You can see it's actually just says WordPress is released under the GPL and then right underneath is the actual GPL itself. So what does that really mean? This is how GPL looks like. It's this huge long document with a bunch of legalists that probably none of you have ever read. Like I only had read maybe like the two first sentences before I researched my talk. So do we really need all this just to say that it's open source? Just to say that you can read the source code? So what else does it say? So let's have a look at that. Okay, the image is not loading. I'm supposed to have this image. Okay, well, Stolman is the guy who basically invented GPL. He would say he would talk about the four freedoms of free software. The first one being the freedom to run the program as you wish for any purpose. We also start from number zero because we are software developers obviously. The second one being the freedom to study how the program works and change it so it does your computing as you wish. This is one of the really important ones because this means that you have the source code and you can study how the source code works and then the other thing is that you can change it. You can modify the source code to be pretty much anything you want. The first one was actually that you can run the code the way you want, but now we can also change the code to do whatever we want and that's really powerful. The third one or the number two one is the freedom to redistribute copies so you can help your neighbour. That means that if you have a copy of WordPress, for example, you can give that copy to anyone else. You can take a copy of it and give it to someone else and nobody's going to come after you. The final one is the freedom to distribute copies of your modified versions. Even if you make changes to the original software, you can give that back to other people. No problem. Great. Cool. So why should you care? I think this is quite an interesting point, this right here. Did you know that all your WordPress code is also GPL? All your WordPress code is also open source. This is because the GPL states that any programme that uses part of another GPL licensed programme is also licensed under the GPL and must contain the GPL licensed. So that means whenever you make a plugin or theme for WordPress, it should always have the GPL licensed with it and along with the GPL licensed that states all the four freedoms that you just saw here, you give all those freedoms to the person that you sell your software or give the software to. So that means they can also change the software and they can give it to someone else. So there's nothing stopping them doing that. But that's a good thing, really, because you want to be able to change the programme that you own. You've bought the piece of software or you've downloaded WordPress or something and you want to do something with it. Usually it's not enough just to have the software and open source is really cool. It really is. But some people don't think so. The ex-CEO of Microsoft has said this about GPL. It is a cancer that attaches itself in an intellectual property, sends to everything it touches. He thinks it's a cancer. But really, I mean, come on, open source is pretty brilliant, really. I mean, we all use things like Linux. If you use WordPress, you pretty much already use Linux. We use Android. We use, even iPhones have loads of GPL software in it. Apple actually ships quite a lot of open source. It's brilliant. Part of the reason why it's so great is that you really, really own the software. Because you have all those rights with the software. You can do pretty much whatever you want with the software. You can edit it. You can modify it. And this is really key to companies who own the software, who want to do something with the software. If it's not open source, if it's a proprietor licence, that gives the original author of the software exclusive rights to, for example, say that nobody else can make changes to it. So you're stuck with the original author for making any changes to the software that you bought. And that's a really bad thing. That's called a vendor lock-in. And that's a terrible thing to happen to a company. And I shouldn't really even have to tell you why that's a bad thing. Because they can set the price to pretty much anything they want. And that's terrible. The second really, really, really cool thing about open source software is quality. Just because lots and lots of people use things like WordPress or Linux, everybody benefits. Just because you find something wrong with work. Maybe WordPress doesn't do something that you need it to do. What do you do? You change it. You make a plug-in or even you might change the source code, the core source code. And then you have an incentive to give it back to the community. Because it's an open source, what you can do is you can give it back to the authors, the maintainers of the software. And then they can include your changes to the software. Which is really cool. Because that's a lot cheaper than having your own version of WordPress or Linux. Because then you just get, in the next update, you get your change as well. Which is much cheaper. Many times this actually happens with WordPress. We've talked before today about feature plug-ins. Things like the emoji. Emoji support for WordPress. That happened when somebody thought, oh, yeah, we should have emojis for my blog. And then the core people thought, okay, that's a cool plug-in. I think we're going to include it in WordPress now. And now everybody has got emoji. And that's great. Maybe the emoji is not that great for all of you. But I think it's still a great thing. And the rest API is another good example of that. It's a feature plug-in that's actually right now in the process of being implemented in the core of WordPress. And this is all because it's open source. Lots of people can make changes to the code and they can make it better. And everyone benefits from that. And just the ability to make it extendable. Because you can modify the GPL code within WordPress. And you can make plug-ins on themes. And you can do anything you want with it. That's really, really, really powerful. One of the greatest things about that is that you can actually sell them. Lots of people think that if a software is open source, you can't sell it. And that's just wrong. The GPL actually states that you can get money out of selling your plug-in, out of selling your code. And that's great. That's the first misconception lots of people have. You can't make money with GPL code. Well, to all of you who think this, just think about these guys. Envato, rule themes or Yoast. I think they're doing pretty okay. All these guys are selling GPL plug-ins or themes for WordPress. And that is great. It's open source. Anyone can go and buy their plug-in and make their modifications and maybe sell it further. But that's okay. This company still managed to make lots of money doing that. And they make great products. Lots of you use those guys. Like WooCommerce, who's our sponsor, actually. The second big misconception is you don't have to pay money for GPL plug-ins. And Mikko actually said some quite good things about this earlier when he was talking about how he makes money out of his plug-in. That is not true. It's true that you can, if you have a copy of the plug-in, you already have all the freedoms of GPL software. You can give it to other people, for example. And you can modify it. And you can use it pretty much however you like. But being GPL doesn't mean that you have to publish your code to everyone else. There's nowhere in the GPL that says you have to put it on GitHub, for example. You can still sell the plug-in code to some person and then he'll just get the GPL plug-in. And that's great. But the problem is that what's the value that they get out of it? Because they would just be able to give the copy to everyone else. And the solution which Mikko already talked about is a premium plug-in model where you actually don't just sell the code. You also give them updates and support and bug fixes. And I think that's a great way to create good business for GPL software. Because that makes your clients really, really happy with the software. Because they're constantly making it better. You get better products that way. A really important point about this is the free-in-free software in GPL doesn't mean that it's free. As in free beer. It means free as in freedom. Right. I forgot about that. Okay. The third misconception is that premium plug-ins and themes aren't GPL. And as we talked about this before, yes they are. Because they use WordPress and they are considered to be part of WordPress. They are derivatives in the legal sense. So even if the plug-in might not have the GPL license in it, even though it should, the GPL still applies to the plug-in. And they are GPL. The founder of WordPress or Automatic said himself a few years back that yes, they are GPL. All plug-ins and themes are GPL. At least the PHP part of it. He makes a distinction that maybe CSS might not be because it doesn't really use the CSS that WordPress does. But it just makes things horrible if you decide to do a different license for your style sheets and different license for your PHP code. And JavaScript back then wasn't that big of a deal. But nowadays if you just, for example, use the REST API, it's a bit debatable, but I think it should be GPL. Plug-ins by definition use the WordPress GPL code base. So that means they are GPL. And so are themes. The fourth misconception about open source software and GPL is that it's developed by hobbyists and students in their basements, something like that, for free. And that's just not true. I mean, think about how WordPress gets developed. Those guys are real professionals. They're really, really good at their job. And people are paying them to do their job, really. I mean, Automatic is a huge company, and they sponsor WordPress development quite a bit. And I mean, come on, you wouldn't do that sort of code all day long for free. I mean, look at the kinds of money that's in open source right now. That's just investments that's gone into open source. This is one study that says hundreds of millions, even billions of dollars go into open source every year. And that's huge. Would you really do that for free? Would you develop WordPress for free? I bet most of you get paid. So open source and GPL are what make WordPress so great. I think we should all just celebrate open source and GPL. Thanks. That's my time.