Cryptocurrency
0Loading crowd target
0Loading crowd target
8correct to beat the crowd
This crypto trivia quiz has 99 free questions with answers and covers the whole story of digital money: the 2008 Bitcoin white paper and the pseudonymous Satoshi Nakamoto, the genesis block, the first pizza bought with bitcoin, how mining, hashing and proof-of-work actually work, Ethereum's smart contracts and the Merge, altcoins, stablecoins, meme coins, NFTs, hot and cold wallets, DeFi, forks and the regulators arguing over which tokens are securities. Easy questions ask what a public key is for and which coin came first; harder ones want the year Ethereum went live, the 1990s precursors to Bitcoin, the Tokyo exchange that collapsed in 2014 and the first country to make bitcoin legal tender. It suits a tech-themed pub quiz, an office icebreaker or anyone who has wondered what their group chat is talking about. Every answer has been checked against a reference source, shown under each question once you have answered.
30 of 99 questions with answers and explanations. Play the quiz
Q 01What is the pseudonym used by the creator or creators of Bitcoin?
Satoshi Nakamoto
Whoever it was went silent in April 2011 and has never moved the roughly one million coins mined in the first year.
Q 02In what year was the Bitcoin white paper, 'Bitcoin: A Peer-to-Peer Electronic Cash System,' published?
2008
It was posted to a cryptography mailing list on Halloween and was ignored by academics, who argued the design could not work; the network went live that January.
Q 03What is the term for any cryptocurrency other than Bitcoin?
Altcoin
It is short for 'alternative coin'; the Wall Street Journal called them 'alternative versions of Bitcoin', which remains the template most of them copy.
Q 04Which 2011 cryptocurrency by Charlie Lee is nicknamed the 'silver to Bitcoin's gold'?
Litecoin
Litecoin, released by Charlie Lee in October 2011, copied Bitcoin's code with faster 2.5-minute blocks and the Scrypt hashing algorithm, which was briefly resistant to specialised mining chips.
Q 05On a proof-of-work blockchain, what is adding blocks and earning new coins called?
Mining
Purpose-built machines race to find a nonce that hashes below the difficulty target; the winner's block reward is currently 3.125 bitcoin.
Q 06What is the very first entry in a blockchain, Bitcoin's dating from 3 January 2009, called?
Genesis
The genesis block, Block 0, was mined by Satoshi on 3 January 2009 with that day's Times headline about a second bank bailout embedded in it, a timestamp and a pointed comment in one.
Q 07Which key must be kept secret because whoever holds it can spend a wallet's funds?
Private key
The private key is the secret that signs transactions, so anyone holding it can spend the wallet's funds; lose it and the coins are unrecoverable, hence 'not your keys, not your coins'.
Q 08Which type of key can be handed out freely so that others can send you cryptocurrency?
Public key
The public key can be shared openly; a wallet address is derived from it, while the matching private key signs outgoing transactions and must never be shared.
Q 09Which kind of cryptocurrency is pegged to a national currency such as the US dollar?
Stablecoin
Stablecoins such as Tether and USDC peg to the dollar with reserves; the algorithmic kind is riskier, and TerraUSD's collapse in 2022 wiped out about $40 billion.
Q 10Which US agency, created in 1934, has claimed jurisdiction over many crypto tokens?
SEC
The SEC, founded in 1934 after the 1929 crash, applies the 1946 Howey test to tokens, asking whether buyers invested in a common enterprise expecting profits from others' efforts; a sister agency treats bitcoin as a commodity.
Q 11Who received the first bitcoin transaction, ten coins from its creator in January 2009?
Hal Finney
Hal Finney, the cypherpunk who built the reusable proof-of-work system RPOW in 2004, received ten bitcoin from Satoshi on 12 January 2009, a day after tweeting 'Running bitcoin'.
Q 12What is the term for a blockchain protocol change that makes old versions incompatible?
Hard fork
A hard fork changes the rules so every node must upgrade or be left on the old chain; a soft fork, by contrast, tightens rules in a way old software still accepts.
Q 13What is the primary purpose of a smart contract on a blockchain?
To run agreed terms automatically
Q 21Which attack did Satoshi's white paper set out to solve without a trusted third party?
Double-spending
Double-spending, using the same coins twice, was the core problem digital cash had to solve; Bitcoin's white paper answers it with a public ledger where the network agrees which conflicting transaction came first.
Q 22What is 'DeFi' an abbreviation for in the cryptocurrency world?
Decentralized Finance
DeFi stands for Decentralized Finance: lending, exchanges and derivatives run as code on permissionless chains with no bank in the middle; the boom took off with the 2020 'DeFi summer'.
Q 23After a 2014 crowdfunding sale, in which year did the Ethereum network go live?
2015
Its purpose is to run agreed terms automatically, as code rather than a legal document; Nick Szabo coined the term in the 1990s, long before there was a blockchain to run one on.
Q 14Which country was the first to adopt Bitcoin as legal tender?
El Salvador
El Salvador's Bitcoin Law, pushed by President Nayib Bukele, took effect on 7 September 2021, making bitcoin legal tender alongside the US dollar; acceptance was made voluntary in January 2025 under an IMF loan deal.
Q 15What is the roughly four-yearly event that cuts Bitcoin's block reward called?
Halving
The halving happens every 210,000 blocks, with the last coin expected around 2140; the 2024 event took the block reward from 6.25 to 3.125 coins.
Q 16What kind of token certifies ownership of digital art on a blockchain?
Non-fungible
A non-fungible token (NFT) is a unique on-chain record that usually points to a file rather than containing it; Beeple's 'Everydays' NFT sold for $69 million at Christie's in March 2021.
Q 17What consensus mechanism is used by Bitcoin to validate transactions and secure its network?
Proof of Work (PoW)
Miners burn electricity hunting for a nonce that hashes below the difficulty target; the idea was borrowed from a 1997 anti-spam scheme by Adam Back.
Q 18Which programmer, then 19, first proposed Ethereum in a 2013 white paper?
Vitalik Buterin
Gavin Wood, Charles Hoskinson, Anthony Di Iorio and Joseph Lubin joined as co-founders; the name came from a list of science-fiction elements on Wikipedia.
Q 19What is the term for crypto storage that stays connected to the internet, handy but more exposed to hackers?
Hot
A hot wallet keeps its keys on an internet-connected device such as an exchange account or phone app; standard advice is to hold only spending money in one and the rest offline.
Q 20Which company, founded in Paris in 2014, makes the Nano line of hardware wallets?
Ledger
Ledger, founded in Paris in 2014, sells the Nano S and Nano X hardware wallets, which keep private keys in a secure chip offline; its 2020 breach leaked customer contact data, not keys.
Its creator picked the name after browsing a list of fictional elements on Wikipedia; the crowdsale had raised about $18 million in bitcoin.
Q 24On Ethereum, transaction fees are priced in a unit named after what?
Gas
Ethereum fees are measured in gas, each operation costing a set amount; since the August 2021 London upgrade (EIP-1559) the base portion of every fee is burned rather than paid to validators.
Q 25Which year saw the first recorded commercial transaction using Bitcoin, famously for two pizzas?
2010
On 22 May 2010 Laszlo Hanyecz paid 10,000 bitcoin for two Papa John's pizzas, the first recorded commercial purchase with bitcoin; the date is now marked as Bitcoin Pizza Day.
Q 26What is the maximum supply of Bitcoin that can ever be mined?
21 million
Just 21 million can ever exist; the last is expected around 2140, after which miners live on fees alone, and a few million are already thought lost forever.
Q 27What is the term for a blockchain's ability to handle an increasing number of transactions?
Scalability
Scalability is the capacity to process more transactions as demand grows; Bitcoin's base layer handles roughly 3 to 7 transactions per second, which is why Lightning and the block-size wars exist.
Q 28What is an 'ICO' in the context of cryptocurrency funding?
Initial Coin Offering
An Initial Coin Offering sells a new token to fund a project; the 2017 boom raised billions on little more than white papers, and regulators later ruled many tokens were unregistered securities.
Q 29Which of these is a digital currency proposed by Nick Szabo in 1998, considered a precursor to Bitcoin?
Bit Gold
Bit Gold, designed by Nick Szabo in 1998 but never built, chained proof-of-work puzzles so closely to Bitcoin's later design that it made Szabo a perennial Satoshi suspect, which he has denied.
Q 30What attack did Bitcoin Gold suffer in 2018, letting thieves reverse exchange deposits?
51% attack
A 51% attack needs a majority of a chain's hashing power; Bitcoin Gold suffered one in May 2018 that reversed about $18 million of exchange deposits, and two more in January 2020.