File sharing is the distribution of digitally held information, including music, media, documents, software.

The image above (BY Matt Britt) is one of the popular representations of the Internet, and gives an idea of how it is possible for computers to be interconnected and communicate.
Thus, many would argue that file sharing is an integral part of the Internet.
One of the most common ways of file sharing today is through P2P or Peer-to-Peer networks. In this, a single computer may be directly connected to various other computers, thus allowing for files to be shared between them.
However, this is considered illegal because file sharing involves making a digital copy of the content being shared. Since this copy is unauthorised by the copyright holder, it amounts to copyright infringement.
For more on file sharing click here.
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