Bitcoin

Bitcoin is a cryptocurrency and worldwide payment system.it is the first decentralized digital currency, as the system works without a central bank or single administrator.The network is peer-to-peer and transactions take place between users directly, without an intermediary. These transactions are verified by network nodes through the use of cryptography and recorded in a public distributed ledger called a blockchain. Bitcoin was invented by an unknown person or group of people under the name Satoshi Nakamoto and released as open-source software in 2009.

https://en.m.wikipedia.org/wiki/Bitcoin