Welcome to the Wikiversity learning project for Fair Use.
Wikiversity has many learning resources that are tutorials for software or that review the utility of software (example). When discussing copyrighted software, it is often useful to provide screenshots as visual aids. Wikiversity has Template:Software-screenshot that can be used as explained at Wikiversity:Uploading files.
In some cases, parts of copyrighted works can be used without permission in order to illustrate commentaries or for education/teaching (see Non-free content). One concern for "fair use" is that it does not disrupt the potential market for or value of the copyrighted work. In the United States, this does not mean that reviews and commentaries cannot be critical. However, at Wikiversity, extra care should be taken when using screenshots to illustrate copyrighted software features that are not viewed as useful to learners. It is not the purpose of Wikiversity to complain about software, but rather, to help learners use software to achieve their learning goals.
It is good practice to find webpages such as this before you upload screenshots of copyrighted software. Microsoft has ten specific guidelines for screen shots of works that they own. For example, the image on the right side of this page shows copyrighted Microsoft software. Microsoft allows fair use of such screen shots for educational purposes such as tutorials. Their instructions say, "You may not use portions of the screen shots". Does this mean that you are required to show the entire captured image as seen on the computer screen when the screen shot was captured? If so, then the image used here to illustrate a screen shot does not meet their requirements. This illustrates the many ambiguities that can arise when fair use is claimed and when attempts are made to follow the wishes of a copyright holder. Wikiversity is always ready to remove fair use images if the copyright holder requests that an image not be used.
Corel also explicitly allows fair use screen shots, but they also have a long list of restrictions and rules.
See Wikiversity:Uploading files#Fair use considerations.