A copyright owner has the exclusive right to reproduce, adapt, publish, perform and display his or her copyrighted work. You regularly can find people posting copyrighted content on the Internet. Sometimes, these people will say that their conduct is not copyright infringement, because they are not making money. That is not really true. Not making money from copyright infringement is a factor in determining whether fair use applies, but it is not dispositive.
If you reproduce, adapt, publish, perform or display a copyrighted work, and you do not meet one of the exceptions (like fair use), you are infringing another's copyright.
The more content that is fair use, the less speech is inhibited. The less content that is fair use, the more speech is inhibited. Larger companies tend to have greater power in getting content removed than smaller companies or individuals. This can lead to abuse, and there is an ongoing debate over copyright misuse inhibiting free speech.
The latest example is a copyright professor who used a copyrighted song during lecture for instruction, and the video of the lecture was posted on YouTube. The recording company of the song complained to YouTube, and YouTube removed the lecture. The professor's lecture is clearly fair use, because it was for nonprofit educational purposes, and would not have affected the market for sales of the song.