Limewire
About
is a free file sharing client for Windows, Mac, OSX, and Linux. Developed in 2000 by Mark Gorton, Lime Wire is said to be the most popular P2P (peer-to-peer) file shareing application with approximately 70 million users.
How it Works
Lime Wire uses Bit Torrent protocal, and accesses a network named Gnutella to provide a wide variety of searches with a timely download speed for users. Security for users is taken seriously, and Lime Wire ensures that they will never bundle spyware, adware, or viruses within their software. However, such promises cannot be ensured with files submitted by others.
Legal Concerns
Lime Wire is legal, however many of the materials distributed through its system are not. In order to use Lime Wire legally, one must obtain permission from the copyright owner of a file for each file put on, or downloaded, from the server. A number of users may knowingly abuse Lime Wire's policies, and for that reason, Lime Wire has made its network, including every downloaded file, trackable.