A cryptocurrency is a peer-to-peer, decentralized, digital currency whose implementation relies on the principles of cryptography to validate the transactions and generation of the currency itself.
Top Currencies based on market capitalization
Bitcoin – $9.3b
Litecoin – $1b
Peercoin – $43.3m
Quark – $12 million
Namecoin
Novacoin
Primecoin
Feathercoin
Anoncoin – $0.14m
Yacoin
Mastercoin
Later on, other major cryptocurrencies, such as Namecoin (an attempt at a decentralized DNS, which would make internet censorship very difficult), Litecoin (which uses scrypt as a proof-of-work, as well as having faster transaction confirmations) and Peercoin (which uses a proof-of-work/proof-of-stake hybrid, and has inflation of about 1%) were also created. Many other cryptocurrencies have been created, though not all have been successful, especially those that brought few innovations.