Copyright law means you cannot use or take any form of media off the internet and use it as your own without permission from the person that owns it. People think you cannot get caught on the internet stealing music and media but you can. The source or law can track down where downloads are coming from and you can be sued or they will shut down the site.
An example of Copyright Infringement is Johnny Cash vs Gordon Jenkins:
Johnny Cash had used the same words as Gordon Jenkins song "Sweet Dream". The only difference between the two was the tuning behind the lyrics, Johnnys sounded more experienced then Gordon's. This is illegal and piracy because although Johhny may have changed the tune to the song it was still the exact same lyrics. There is a certain amount that you have to change to something to consider it being your own work.
