Gold → fiat → Bitcoin → Zcash
How money works—and why it keeps changing.
In many societies, money long meant weighed or stamped metal. Then governments tied their currencies to gold. On 15 August 1971 the United States closed the “gold window”, and the dollar stopped being convertible into gold—even for foreign governments. Bitcoin, launched after the 2008 crisis, offered money with no central issuer; Zcash added private payments. This library follows that story—and shows where each new money worked, and where it didn’t.
The story in four steps
- 01 · GoldHow a metal became moneyFrom ornament and weighed metal to stamped coins and the gold standards.
- 02 · After Gold1971: the gold promise breaksNixon closes the gold window, currencies float, and money rests on law and institutions.
- 03 · BitcoinMoney without an issuerWhat Bitcoin solved, how it is used, and what happened when countries adopted it.
- 04 · ZcashPrivate digital cashPayments that can be verified without publishing who paid whom, or how much.
Quick answers
What is fiat money?
Fiat money is a state-issued currency with no fixed legal promise to redeem it for a set weight of gold or any other commodity. People use it because of law, tax obligations, payment systems and confidence. Its issuer may still hold gold reserves.
Glossary: fiat money →Why did the gold standard end?
It ended in stages, not in one moment. Britain suspended gold conversion in September 1931 after a run on sterling drained its reserves. The United States suspended domestic dollar–gold conversion in 1933 after a banking crisis and gold outflows. On 15 August 1971 President Nixon closed the gold window, ending official conversion of foreign governments’ dollars at $35 an ounce.
Read: The Gold Standard Era, 1717–1971 →Did making Bitcoin legal tender work in El Salvador?
El Salvador’s 2021 Bitcoin Law required Bitcoin to be accepted alongside the US dollar. After the IMF urged it to narrow Bitcoin’s role, Decree 199 (January 2025) made private acceptance voluntary and ended Bitcoin tax payments. The law still says “curso legal”, but the IMF says it no longer has the essential features of legal tender. Whether payments, inclusion or public finances improved has not been shown with comparable measures.
Read: Countries that adopted Bitcoin →What is Zcash, and where does it fit?
Zcash is a public cryptocurrency network launched in October 2016; ZEC is its native unit. Shielded payments can be checked as valid without publicly revealing sender, recipient or amount—a real gain over a fully transparent ledger. Privacy alone does not make ZEC a unit for prices, wages or debts, and whether a ZEC economy could work is unproven.
Read: What Zcash is, and what is live →Follow a question
Four jobs money does
Store of value
Keeps buying power over time.
Medium of exchange
Pays for goods and services.
Unit of account
States prices, wages and debts.
Settlement asset
Settles debts between people, banks and governments.
No money has to do all four jobs. To compare two kinds, ask what you actually hold, who owes you, and who controls the transfer.
Compare what you hold
Cash is a promise from its issuer. A bank balance is a claim on your bank. Physical gold is an asset someone has to store. Self-custodied Bitcoin is only as safe as your keys. An exchange balance or a stablecoin adds one more company you have to trust. Compare them side by side →
Where does new money come from? Follow four £100 transactions, from a bank loan to QE →
How we handle evidence
Every chapter cites its sources. When a figure can’t yet be tied to an exact source, we leave it out rather than guess. How this library is built →