Internet copyright infringement is the unauthorized use of online copyrighted material which violates the exclusive rights of the copyright holder. Exclusive rights may include the right to make derivative works, or the right to perform or reproduce the copyrighted work. Online Internet copyright infringement is also commonly referred to as "piracy," especially in regard to the unlawful uploading, downloading, and sharing of media files such as mp3 music files or pirated movies and computer software. File sharing programs such as Napster and Kazaa are routinely used to engage in Internet copyright infringement, with users copying and sharing a wide variety of copyrighted material. The unauthorized use of copyrighted text is another common form of Internet copyright infringement. Articles, novels, screenplays, and other forms of copyrighted text are commonly misappropriated on the Internet In some cases, Internet users may be unaware that they have violated a copyright, and the situation can be easily remedied by contacting the offender. In other cases, web users may willfully violate a copyright. Substantial monetary penalties for willful copyright violations have been issued by the courts in the past, and many copyright holders continue to push for tougher laws.