Cryptocurrency types include Bitcoin (BTC), the first and most recognized digital currency, Ethereum (ETH), known for smart contracts and decentralized applications, and Stablecoins like Tether (USDT), which are pegged to fiat currencies. There are also Altcoins (alternative cryptocurrencies), such as Litecoin and Ripple (XRP), Privacy coins like Monero, and Tokens used within specific blockchain ecosystems.