Peercoin, also known as PPCoin or PPC, is a peer-to-peer cryptocurrency utilizing both proof-of-stake and proof-of-work systems.
Peercoin is based on an August 2012 paper which listed the authors as Scott Nadal and Sunny King. King, who also created Primecoin, is a pseudonym.The Peercoin source code is distributed under the MIT/X11 software license.
In the proof-of-stake system, new coins are generated based on the holdings of individuals. In other words, someone holding 1% of the currency will generate 1% of all proof-of-stake coin blocks. This has the effect of making a monopoly more costly, and separates the risk of a monopoly from proof-of-work mining shares.