Glossary
Zero-Knowledge Proof
A zero-knowledge proof lets one party convince another that a specific statement is true — a person is over a certain age, an account holds sufficient funds — without revealing any of the underlying data that makes the statement true. The verifier ends up genuinely certain the statement holds, but learns nothing else: not the actual age, not the actual balance, nothing beyond the truth of the specific fact being proven.
This changes what an authorization check can require without also requiring disclosure: a system can demand proof of eligibility for something without needing to actually collect or even see the sensitive underlying data that eligibility depends on, which is a meaningfully different and more protective posture than the usual pattern of collecting the data and then trusting the system to guard it responsibly afterward.