What Does Peer-To-Peer File Sharing (P2P File Sharing) Mean?
Peer-to-peer (P2P) file-sharing is enabled by software that treats users as both clients and servers. Users who engage in file-sharing over a certain piece of P2P software typically do not communicate with a single central server, as these programs tend to be very de-centralized and the users tend to communicate directly with one another.
Techopedia Explains Peer-To-Peer File Sharing (P2P File Sharing)
The origin of peer-to-peer file-sharing is believed to exist in the Bulletin Board System (BBS), which was like an intranet that could be dialed into using modems in order to exchange files and messages. Other technology (such as Usenet) and file formats (such as RAR) further enabled file-sharing to some extent over the years, however it was not until the advent of Napster (a prominent file-sharing platform that became very controversial) that file-sharing became a mainstream activity. After Napster was shut down in 2001, a number of other file-sharing platforms sprouted up in its place, some of which are still widely in use.