P2, or Peer-to-Peer, refers to a decentralized network model where participants, or peers, interact directly with each other without the need for a central server. This system allows users to share resources, such as files or computing power, directly, making it efficient and often more resilient to failures. In a P2P network, each participant can act as both a client and a server, enabling them to send and receive data. This model is commonly used in applications like file sharing and cryptocurrencies, where users can transact or share information securely and anonymously.