(eg bitcoin)

A cryptocurrency (or crypto currency) is a medium of exchange using cryptography to secure the transactions and to control the creation of new units. Cryptocurrencies are a subset of alternative currencies, or specifically of digital currencies. Bitcoin became the first decentralized cryptocurrency in 2009. Since then, numerous cryptocurrencies have been created. These are frequently called altcoins, as contraction of bitcoin alternative.  Cryptocurrencies typically feature decentralized control (as opposed to a centralized electronic money system, such as PayPal) and a public ledger (such as bitcoin's block chain) which records transactions. - wikipedia

CryptoCurrency and associated protocols can be seen as a language to manage trust and share value within a community based on the maths of cryptography and a common (public) ledger.

It does to real-world value-information ("money") as http-and-the-internet did to information-accessibility.

The underlying blockchain mechanism can be used may different applications like powering Decentralized Autonomous Organizations (DAOs).

It can be the basis to a lot of real world change within our societies,
it is so much more then money - it knows no boundaries...


Public/Common Ledger

Keeps account of the value exchange within a community.

Using the bitcoin blockchain as an example...

The block chain is a public ledger that records bitcoin transactions. A novel solution accomplishes this without any trusted central authority: maintenance of the block chain is performed by a network of communicating nodes running bitcoin software. Transactions of the form payer X sends Y bitcoins to payee Z are broadcast to this network using readily available software applications. Network nodes can validate transactions, add them to their copy of the ledger, and then broadcast these ledger additions to other nodes.The block chain is a distributed database; in order to independently verify the chain of ownership of any and every bitcoin (amount), each network node stores its own copy of the block chain. Approximately six times per hour, a new group of accepted transactions, a block, is created, added to the block chain, and quickly published to all nodes. This allows bitcoin software to determine when a particular bitcoin amount has been spent, which is necessary in order to prevent double-spending in an environment without central oversight. Whereas a conventional ledger records the transfers of actual bills or promissory notes that exist apart from it, the block chain is the only place that bitcoins can be said to exist in the form of unspent outputs of transactions - wikipedia - more...
Mining Machines As at APR2015, the top mining computer does
5,000,000,000,000 hash (SHA256) calculations per second - more...


bitcoin - wikipedia
crytocurrency - wikipedia
DAO - wikipedia
The Age of CrytoCurrencies
PROJECTS & SERVICES, wikipedia, wikipedia