Intellectual Property are creations of the mind. They are songs, books, scientific formulas, plays, drawings, emails, Facebook posts, or anything that is written, recorded (audio and visual), drawn, invented, or created.
All intellectual property is protected by copyright even if it is not registered or does not have the copyright symbol ©.
Fair Use permits the limited use of the works of others in certain circumstances. These are only general rules rather than definitive ones. This was done to avoid limiting its definition and allowing it to be open to interpretation much like free speech.
You need to consider four factors when deciding if it qualifies for Fair Use.
1. Purpose and Character of Use
2. Nature of the Copyrighted Work
3. Amount of the Work Used
4. Effect of Use on the Market