A cryptocurrency (or crypto currency) is a digital asset designed to work as a medium of exchange that uses strong cryptography to secure financial transactions, control the creation of additional units, and verify the transfer of assets.

Cryptocurrencies Coins — Many coins of various cryptocurrencies

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Cryptocurrency is an internet-based medium of exchange which uses cryptographic functions to conduct financial transactions. Cryptocurrencies leverage blockchain technology to gain decentralization, transparency, and immutability.

What’s cryptocurrency?

Financial Technology concept — Financial technology concept.

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The definition of a cryptocurrency is a digital currency built with cryptographic protocols that make transactions secure and difficult to fake. The most important feature of a cryptocurrency is that it is not controlled by any central authority: the decentralized nature of blockchain makes cryptocurrency theoretically immune to the old ways of government control and interference. Cryptocurrencies make it easier to conduct any transactions, for transfers are simplified through use of public and private keys for security and privacy purposes. These transfers can be done with minimal processing fees, allowing users to avoid the steep fees charged by traditional financial institutions.
However, the latest news on cryptocurrencies indicates that because cryptocurrencies are devoid of a central repository, a digital cryptocurrency balance can be wiped out by a computer crash, a hack, and other unexpected events.

Rules for cryptocurrency

According to Jan Lansky, a cryptocurrency is a system that meets six conditions:

The system does not require a central authority, its state is maintained through distributed consensus.
The system keeps an overview of cryptocurrency units and their ownership.
The system defines whether new cryptocurrency units can be created. If new cryptocurrency units can be created, the system defines the circumstances of their origin and how to determine the ownership of these new units.
Ownership of cryptocurrency units can be proved exclusively cryptographically.
The system allows transactions to be performed in which ownership of the cryptographic units is changed. A transaction statement can only be issued by an entity proving the current ownership of these units.
If two different instructions for changing the ownership of the same cryptographic units are simultaneously entered, the system performs at most one of them.

The first cryptocurrency, Bitcoin

Bitcoin is a digital currency created in January 2009. It follows the ideas set out in a whitepaper by the mysterious and pseudonymous developer Satoshi Nakamoto, whose true identity has yet to be verified. Bitcoin offers the promise of lower transaction fees than traditional online payment mechanisms and is operated by a decentralized authority, unlike government-issued currencies.

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There are no physical bitcoins, only balances kept on a public ledger in the cloud, that – along with all Bitcoin transactions – is verified by a massive amount of computing power. Bitcoins are not issued or backed by any banks or governments, nor are individual bitcoins valuable as a commodity. Despite it not being legal tender, Bitcoin charts high on popularity, and has triggered the launch of hundreds of other virtual currencies collectively referred to as Altcoins.