Cryptocurrency uses cryptography to conduct financial transactions securely and decentralize control. While initially controlled by a single founder, it has grown to include many alternative coins (altcoins) like Ethereum and Litecoin. Transactions are recorded on a public blockchain to prevent fraud. Cryptocurrencies offer low fees, global access, and pseudonymity compared to traditional currency but are subject to market volatility. Adoption may help the global economy through increased activity, financial access, and transparency of transactions.