Cryptocurrency is a digital or virtual currency that uses cryptography for security and is decentralized, meaning that it is not controlled by any central authority such as a government or financial institution. Cryptocurrencies are based on a distributed ledger technology called blockchain, which allows for secure and transparent peer-to-peer transactions.

Cryptocurrencies are often used as a medium of exchange and can be bought, sold, and traded on online exchanges. They can also be used to purchase goods and services from merchants who accept them. Some popular cryptocurrencies include Bitcoin, Ethereum, and Litecoin.

Cryptocurrencies are decentralized, meaning that they are not subject to the same regulations as traditional fiat currencies and are not backed by any physical assets or governments. This has made them attractive to some users as a means of exchange that is not controlled by a central authority, but it also means that they are subject to significant price volatility and may not be as stable as traditional currencies.