Cryptocurrency
Cryptocurrency is a type of digital asset that uses cryptographic techniques and distributed ledger technology (DLT) or similar technology to record, secure, and transfer ownership or transaction information. Cryptocurrencies are generally privately issued rather than issued by a central bank or government.
The term is commonly used for digital assets that operate through decentralized or distributed networks, particularly those based on blockchain technology. Cryptocurrencies can be used for payments, transfers, trading, investment, and other purposes.
Characteristics
Cryptocurrencies commonly have the following characteristics:
- digital rather than physical form;
- use of cryptographic techniques;
- use of distributed ledgers or similar technologies;
- electronic transfer between participants;
- reliance on software protocols and network participants;
- absence of a conventional central issuer in many cryptocurrency systems;
- market-based valuation for many cryptocurrencies.
The characteristics vary among individual cryptocurrencies.
Cryptography
Cryptography is used to secure cryptocurrency systems and transactions.
Cryptographic mechanisms can be used to:
- authenticate transactions;
- control access to assets;
- secure transaction records;
- establish ownership through private keys;
- protect the integrity of transaction data.
Users generally control cryptocurrency holdings through cryptographic keys. Loss or compromise of a private key can result in loss of control over the associated assets, depending on the system.
Distributed ledger technology
Distributed ledger technology (DLT) allows transaction records to be maintained and synchronized across multiple participants in a network.
In a cryptocurrency system, the ledger records transactions and helps establish which units have been transferred and to whom.
Distributed ledgers can reduce reliance on a single centralized record keeper, although the degree of decentralization varies among systems.
Blockchain
A Blockchain is a type of distributed ledger in which transactions are organized into blocks that are cryptographically linked.
Many major cryptocurrencies use blockchain technology, although not every digital asset or distributed-ledger system necessarily uses a conventional blockchain.
Bitcoin, for example, uses a blockchain-based distributed ledger to record transactions.
Decentralization
Many cryptocurrencies are designed to operate without a central authority controlling the transaction ledger.
Instead, transaction validation and record keeping may be performed by a distributed network of participants according to predefined protocol rules.
The degree of decentralization can vary substantially between cryptocurrency systems.
Consensus mechanisms
Cryptocurrency networks require mechanisms for determining which transactions are valid and how the distributed ledger should be updated.
Common consensus mechanisms include:
Proof-of-work systems generally use computational work to help secure the network, while proof-of-stake systems use economic stakes and validators to participate in transaction validation.
The design and security characteristics of consensus mechanisms differ among cryptocurrency networks.
Mining
Mining is a process used by certain cryptocurrency networks, particularly proof-of-work systems, to validate transactions and add new blocks to a blockchain.
Participants known as miners use computational resources to perform the required work.
In some systems, successful miners may receive newly issued cryptocurrency units and transaction fees as rewards.
The importance and operation of mining depend on the underlying consensus mechanism.
Validators
In proof-of-stake and other systems, validators participate in maintaining and updating the distributed ledger.
Validators may be required to commit resources to the network and follow protocol rules when validating transactions or proposing blocks.
The role of validators differs from that of miners in proof-of-work systems.
Digital wallets
A cryptocurrency wallet is a software, hardware, or other mechanism used to manage the cryptographic keys associated with cryptocurrency holdings.
Wallets can be used to:
- receive cryptocurrency;
- send cryptocurrency;
- manage private keys;
- interact with blockchain applications.
A wallet does not necessarily store cryptocurrency in the same way that a physical wallet stores cash. The underlying assets are represented on the relevant distributed ledger, while the wallet manages the credentials used to control them.
Private and public keys
Cryptocurrency systems commonly use cryptographic key pairs.
A public key or related address can be used to receive assets, while a private key is used to authorize transactions or otherwise demonstrate control over the associated assets.
The exact cryptographic structure varies between cryptocurrency systems.
Transactions
A cryptocurrency transaction generally records the transfer of cryptocurrency from one address or account to another.
A simplified representation is:
Once a transaction has been validated and recorded according to the relevant protocol, it becomes part of the network's transaction history.
Transaction fees
Cryptocurrency networks may charge transaction fees.
Fees can compensate network participants for processing transactions and, in some systems, contribute to network security.
The amount of a transaction fee can depend on factors such as:
- network congestion;
- transaction size;
- network design;
- computational requirements;
- user-selected fee parameters.
Supply mechanisms
Cryptocurrencies can use different mechanisms for controlling their supply.
These may include:
- fixed maximum supply;
- predetermined issuance schedules;
- inflationary issuance;
- programmed supply reductions;
- governance-based changes.
For example, the Bitcoin protocol specifies a maximum supply of 21 million bitcoins.
Types of cryptocurrency
Cryptocurrencies and related cryptoassets can be classified according to their characteristics and intended functions.
Examples include:
- unbacked cryptocurrencies;
- stablecoins;
- utility tokens;
- governance tokens;
- asset-backed cryptoassets;
- tokenized traditional assets.
The broader term cryptoasset encompasses categories that may not meet the narrower meaning commonly associated with cryptocurrency.
Bitcoin
Bitcoin is a cryptocurrency introduced in 2009 that uses a decentralized, blockchain-based system.
It was designed to enable electronic transfers without requiring a conventional central intermediary to maintain the transaction ledger.
Bitcoin is one of the most widely recognized cryptocurrencies.
Ethereum
Ethereum is a blockchain platform whose native cryptoasset is Ether (ETH).
Unlike systems designed primarily for transferring a cryptocurrency, Ethereum also supports programmable applications through smart contracts.
This functionality has contributed to the development of decentralized finance (DeFi) and other blockchain applications.
Stablecoins
Stablecoins are cryptoassets designed to maintain a relatively stable value against a specified asset, currency, or basket of assets.
They are a category of cryptoasset rather than being synonymous with cryptocurrencies generally. :contentReference[oaicite:5]{index=5}
Stablecoins may use different stabilization mechanisms, including:
- fiat-currency reserves;
- other financial assets;
- cryptocurrency collateral;
- algorithmic mechanisms.
The effectiveness and risks of these mechanisms vary.
Uses
Cryptocurrencies can be used for:
- electronic payments;
- cross-border transfers;
- investment;
- trading;
- speculation;
- decentralized applications;
- digital-asset transfers;
- access to blockchain-based services.
The actual use of a cryptocurrency depends on its technical design, ecosystem, market acceptance, and applicable regulations.
Cryptocurrency markets
Cryptocurrencies can be bought and sold through cryptocurrency exchanges and other trading platforms.
Market participants may trade cryptocurrencies against:
- national currencies;
- stablecoins;
- other cryptocurrencies.
Cryptocurrency markets can operate continuously, including outside the conventional trading hours of traditional securities exchanges.
Price and volatility
Cryptocurrency prices are determined by market supply and demand.
Many cryptocurrencies have experienced substantial price volatility. Factors affecting prices may include:
- market sentiment;
- adoption;
- technological developments;
- regulatory changes;
- liquidity;
- supply mechanisms;
- macroeconomic conditions;
- speculative activity.
The value of a cryptocurrency is therefore not necessarily stable or guaranteed.
Cryptocurrency and money
Cryptocurrencies are sometimes described as forms of digital money, but the terms are not synonymous.
Money traditionally performs three functions:
- medium of exchange;
- unit of account;
- store of value.
Many cryptocurrencies have not consistently performed all three functions at the scale and stability associated with conventional national currencies. The IMF has noted that cryptoassets are privately issued and denominated in their own units of account.
Cryptocurrency and fiat currency
Fiat currencies are generally issued by governments or central banks and are recognized as official currency within their respective jurisdictions.
Cryptocurrencies are generally privately issued and operate through technological protocols rather than conventional central-bank monetary systems.
A cryptocurrency can therefore coexist with a national currency without being legal tender in that jurisdiction.
Cryptocurrency and central bank digital currency
A central bank digital currency (CBDC) is a digital form of central-bank money.
CBDCs differ from cryptocurrencies in several important respects.
CBDCs are issued by central banks and represent liabilities of those institutions, whereas cryptocurrencies are generally privately issued digital assets.
Decentralized finance
Decentralized finance (DeFi) refers to financial activities conducted through software protocols and smart contracts built on distributed-ledger networks.
Cryptocurrencies and other cryptoassets can be used within DeFi applications for activities such as:
- lending;
- borrowing;
- trading;
- liquidity provision;
- collateralization.
DeFi therefore represents a broader ecosystem than cryptocurrency itself.
Risks
Cryptocurrency ownership and use can involve significant risks, including:
- price volatility;
- loss of private keys;
- theft;
- fraud;
- cybersecurity attacks;
- operational failures;
- market manipulation;
- liquidity risk;
- counterparty risk;
- regulatory uncertainty.
The risks vary according to the cryptocurrency, service provider, technology, and method of custody.
Regulation
The regulatory treatment of cryptocurrencies differs substantially among jurisdictions.
Regulatory frameworks may address:
- trading platforms;
- custody;
- payments;
- taxation;
- consumer protection;
- anti-money laundering;
- market integrity;
- financial stability.
International financial authorities generally distinguish among different categories of cryptoassets because their characteristics and risks differ.
Taxation
Cryptocurrency transactions may have tax consequences depending on the jurisdiction and the nature of the transaction.
Potentially relevant events may include:
- buying and selling;
- exchanging one cryptoasset for another;
- receiving cryptocurrency for goods or services;
- mining;
- staking;
- other forms of cryptoasset income.
The applicable tax treatment varies by jurisdiction.
Environmental considerations
Some cryptocurrency networks, particularly proof-of-work systems, require substantial computational resources.
The environmental impact of a cryptocurrency network depends on factors including:
- consensus mechanism;
- electricity consumption;
- energy sources;
- hardware efficiency;
- network activity.
Proof-of-stake systems generally use substantially less direct computational energy for consensus than proof-of-work systems, although the overall environmental impact depends on the specific network.
Importance
Cryptocurrency represents an important development in digital finance and distributed-ledger technology. It combines cryptographic techniques, digital assets, and distributed networks to enable the electronic transfer and management of value without necessarily relying on a conventional central intermediary. Its development has influenced financial technology, payments, investment, decentralized finance, and discussions concerning the future structure and regulation of money and financial markets.