Definition
A cryptocurrency is a digital currency whose ledger is maintained by a distributed network of nodes using cryptographic proof rather than by a single central authority. Bitcoin was the first and remains the most widely accepted, but Ethereum, Litecoin, Monero, and many others are also in use. From a VPN-subscription perspective, the key property is that some cryptocurrencies allow payment without linking the transaction to a verified real-world identity.
Pseudonymous vs Anonymous
Bitcoin is often called anonymous, but it is more accurately described as pseudonymous: every transaction is permanently recorded on a public ledger, and sophisticated chain-analysis firms can de-anonymize many wallets by linking them to exchanges that perform identity checks. For genuine anonymity, privacy coins like Monero (default-private) and Zcash (optionally private) offer stronger guarantees by hiding amounts, senders, or both.
Why VPNs Accept It
Privacy-focused VPN providers like Mullvad, IVPN, and Proton VPN accept cryptocurrency precisely so that users can subscribe without ever providing a name, address, email, or payment card. Combined with anonymous account creation (Mullvad uses only a randomly generated account number with no email at all), this closes the loop: the provider literally cannot identify the human behind the account.