PayPal, officially PayPal Holdings, Inc., is a popular worldwide online payment system. The company facilitates online money transfers among diverse parties, including firms and individuals, allowing payments for goods and services, online auctions, requests for funds, and charitable donations. PayPal lets users send funds without sharing bank account information with unknown buyers and sellers. In 2016, it was the largest of the peer-to-peer payment systems on the Internet, although others include Amazon Payments, Apple Pay, Softpay, and a variety of digital wallets. This entry examines PayPal’s scope and mandate, history, and controversies.