Cryptocurrencies are digital or virtual currencies that use cryptography for secure, decentralized transactions. They function on blockchain technology, a distributed and immutable ledger that records all transactions across a network of computers. Each cryptocurrency operates independently with its own rules and protocols.

In a digital transaction, when a user initiates a transfer of cryptocurrency to another party, the transaction is broadcast to the network and verified by a process known as mining or consensus mechanisms. This involves solving complex mathematical puzzles to validate the transaction and add it to the blockchain. Once verified, the transaction becomes a permanent part of the public ledger.

Cryptocurrencies eliminate the need for intermediaries like banks, as the blockchain ensures transparency and security without central control. Ownership and transactions are pseudonymous, with users identified by cryptographic addresses. Cryptocurrencies have gained attention for their potential to revolutionize financial systems and enable borderless, efficient, and censorship-resistant transactions.