When trying to determine if you can use any given material, try to think systematically about the material and the nature of your use of it.
Start any analysis with two very basic questions:
If you determine that copyright will come into play, figure out if your use is permitted by an existing exception (like Fair Use, the Classroom Use Exemption, or the TEACH Act). If so, you can use it legally.
When thinking about these exceptions it can be useful to keep in mind that in the face-to-face classroom the two exceptions that are likely to apply are the Classroom Use Exception and Fair Use. In the online classroom, most often you will be looking to Fair Use, though in some cases the TEACH Act will apply. If you have determined that your use would exercise one of the exclusive rights of copyright, the work is copyrightable and still under copyright and no exceptions applies to your use, at that point you will need to seek permission. Remember, you're not in this alone: you can always contact us for help.