Bitcoin glossary
Privacy (on-chain)
Bitcoin is pseudonymous, not anonymous — every transaction is public forever.
Bitcoin’s ledger is fully public: every transaction, forever. What it does not contain is names — addresses are pseudonyms. Privacy therefore depends on keeping addresses unlinked from identity, which KYC purchases, address reuse, and careless consolidation all undermine.
Practical hygiene: fresh addresses per payment, coin control, and understanding that chain-analysis firms make deanonymization a business. Lightning improves payment privacy substantially.