Programmable Privacy

Programmable privacy describes blockchain systems in which privacy is not all-or-nothing but can be configured by developers and users: an application can keep some data, such as balances or identities, confidential while making other data public, and can allow selective disclosure to chosen parties such as auditors. This contrasts with fully transparent chains, where all activity is visible, and with a privacy coin that applies the same privacy rules to every transaction. The approach typically relies on zero-knowledge proofs, which prove a statement is true without revealing the underlying data, and sometimes on encryption methods that allow computing on hidden values. Several privacy-focused networks use the phrase for their design. Supporters see it as a way to meet both user privacy needs and regulatory demands; critics note that the tools are complex and that their privacy depends on correct implementation. Also see privacy-enhancing technologies and blockchain's privacy paradox.