To know how the Open Source Software vendors get paid, first you need to have a clear vision and understanding on what is Open Source Software (OSS). You are probably under the wrong idea, that “Open Source Software is free software”. However, this is not the case. Once you go into Open Source world, this has to be in your head, “Open Source Software is not free software”, and if you consider every Open Source Software to be free, you are jeopardizing your career, you are jeopardizing your company; it’s just illegal. When some programmer sits down to write a program, they provide you the source code so that you can see how the program was written. So the very definition of Open Source Software is that you are allowed to see the source code, you are allowed to see how the software was actually created. So, don't get the wrong assumption that every Open Source Software is free. It actually means that you are allowed to see the source code. Majority of Open Source Software happens to be free, but that doesn't mean every Open Source Software is free. So now, since you know what Open Source Software is, the next thing you need to know is how they get paid. One does not simply write software code on his own and distribute the source code for free. So, how do they actually get paid? Some ways how these Open Source vendors get paid are listed and explained below: Donations There are thousands of people donating for Open Source Software. If an OSS vendor can build a loyal user-base who can’t live without their software, some users will donate to keep vendors afloat. Some will donate a LOT. The difficulty is building that loyalty. Charge for the support The MySQL database model is an Open Source  database management software and is 100% free, whether it is for personal use or commercial use or non-profit. The reason behind it is very clever. MySQL business model stated that their idea was to give away all the software for free and then when the user will need help or support, then he/she will call them and pay them money for their support for the database that he/she is using. So, basically you get the MySQL database for free. You see how powerful it is, and then you go “hmm... I need MySQL training”. So, you go to them, pay them and get training. So that’s how they get the money. Free for personal or non-commercial use, but for commercial use, you need to pay Lots of Open Source  Software vendors that are out there want computer geeks to play with the software, use it at home or a computer lab and not have to worry about the legal licensing. In Microsoft, even if you are playing around with the software in your computer lab, you may actually have licensing issues. You may get sued even if you are just trying to play around with the software due to the licensing issue. So the idea is, if you are a computer geek and you want to play around with the Open Source Software or install it in the computer lab to see how it works, it is absolutely and utterly free. The problem where you can get into is that, as soon as you take that server in the production environment, or commercial business environment, you now own a licensing fee. And these licensing fees may even be thousands of dollars. So, be very careful about these. The bottom line is that, once you use the Open Source Software for the commercial purpose, you need to buy the license. By selling it This basically means that if you want the product, you pay the licensing fee and you buy it just like other commercial software like Adobe, Microsoft, etc. The difference with Open Source Software in this model where you just purchased the software is that you can see the source code. So, if you buy the Windows OS, they are not going to give you the source code. With Open Source Software, you buy the license and then you get to see the code. The one thing that you have to be very careful about is that although you see the code, you have to understand what your rights are to the code because this is copyrighted or trademarked or whatever. Although you are allowed to see the source code, you may not have right to modify the code. So, you buy the software and see the source code but changing the code may be illegal. Payment of recurring contract to use the software. To make this clear, some Linux vendors provide the OS software for free; you can play around with it and do whatever you want to do with it. It's amazing. But in order to actually use it, you have to pay between $100 to $1000 per year as per support contract. So, this basically sums up that you need to pay for the software on yearly basis just to get the support. Paid Plugins and Enhancements Consider one of the most successful web systems, WordPress. It’s offered free of charge for anyone to use and modify, but there are plenty of WordPress professionals who make a living by creating and selling WordPress plugins, themes, etc. I may be wrong in some points above or the points may be unclear. If so, please have your say on the comment section. Thanks for reading!  (Author Biography: Sagar Giri is a fifth semester student at DWIT.)