Open Source and Licensing Flashcards

Which of the following license types is characterized by the 'copyleft' provision, requiring that derivative works also be distributed under the same or an equivalent license?

Answer: GNU General Public License (GPL)

The GNU General Public License (GPL) is the most well-known copyleft license. A key feature of copyleft is that it requires any software that is modified or extended from the original work to be released under the same license, ensuring the software remains free.

A developer wants to use an open-source library in their new proprietary, closed-source application. They need a license that allows them to use the code without requiring them to release their own source code. Which license type would be most suitable?

Answer: A permissive license like MIT

Permissive licenses, such as the MIT or Apache licenses, place minimal restrictions on how the software can be used, modified, and redistributed. They do not have a 'copyleft' provision, making them ideal for inclusion in proprietary, closed-source commercial software.

What is a primary difference between the Apache 2.0 license and the MIT license?

Answer: The Apache 2.0 license includes an express grant of patent rights, while the MIT license does not.

A key feature of the Apache 2.0 license is that it includes an explicit grant of patent rights from contributors to users. The MIT license is much simpler and does not explicitly address patent rights, which is a key reason some projects and corporations prefer the Apache license.

The Free Software Foundation (FSF) defines four essential freedoms for free software. Which of the following is NOT one of those freedoms?

Answer: The freedom from any cost associated with the software.

The FSF's definition of free software focuses on liberty, not price. It defines free software by four essential freedoms: the freedom to run the program, to study and change it, to redistribute copies, and to distribute copies of your modified versions. Free software can be sold.

A graphic designer creates an icon set and wants to allow others to use it for free, even in commercial projects. However, they want to ensure that any modified versions of the icons are also shared freely under the same terms. Which Creative Commons license should they use?

Answer: CC BY-SA (Attribution-ShareAlike)

The Creative Commons Attribution-ShareAlike (CC BY-SA) license allows others to remix, adapt, and build upon the work even for commercial purposes, as long as they give credit and license their new creations under the identical terms. This 'ShareAlike' component is a form of copyleft for creative works.

When you use software licensed under the GNU GPLv2, what is a key obligation if you distribute a modified version of that software?

Answer: You must make the source code of your modifications available under the GPLv2.

The GNU GPL is a 'copyleft' license, which means that if you create a derivative work (e.g., by modifying the source code) and distribute it, you must also license your derivative work under the GPL. A core part of this is making the corresponding source code available to the recipients.