Cryptocurrency
0Loading crowd target
0Loading crowd target
8correct to beat the crowd
This crypto trivia quiz has 128 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 128 questions with answers and explanations. Play the quiz
Q 01Which crypto slang for refusing to sell began as a typo in a 2013 Bitcoin forum post?
HODL
HODL was a mistyped 'hold' in a December 2013 Bitcointalk post titled 'I AM HODLING', written mid-crash by a user who said he'd had some whisky; fans later recast it as 'hold on for dear life'.
Q 02Bitcoin's white paper appeared in October 2008, weeks after which Wall Street bank went bankrupt?
Lehman Brothers
Lehman Brothers filed for bankruptcy on 15 September 2008; the white paper followed on 31 October, pitching online payments sent directly from one party to another with no financial institution in between.
Q 03What is the term for any cryptocurrency other than Bitcoin?
Altcoin
Altcoin is short for 'alternative coin'; because Bitcoin's code is free for anyone to copy, many of them began as copies that reused it with a few settings changed.
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 but targets a block every 2.5 minutes, so its payments confirm four times faster.
Q 05What is the slang for developers hyping a token, then vanishing with investors' money?
Rug pull
Rug pull is the slang; in 2021 a token cashing in on the TV hit Squid Game soared, then fell to almost nothing as its developers made off with millions of dollars.
Q 06The first block of any blockchain, mined for Bitcoin on 3 January 2009, is known as the what block?
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 lets whoever holds it 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 stuck for good, because the network accepts no other proof of ownership.
Q 08A Bitcoin address that others send coins to is a hashed form of which key?
Public key
The public key is usually run through a hash to make the address, so an address can be posted anywhere; coins sent to it stay put until a matching digital signature unlocks them.
Q 09Which kind of cryptocurrency is pegged to a national currency such as the US dollar?
Stablecoin
Stablecoins usually hold reserves such as dollars and Treasury bills to keep the peg; the algorithmic kind has no such backing, and TerraUSD's collapse in May 2022 wiped out more than $40 billion.
Q 10Which US regulator sued Ripple in 2020 and both Coinbase and Binance in 2023 over crypto tokens?
SEC
The SEC argued the tokens were investment contracts under the 1946 Howey test, which asks whether buyers put money into a common enterprise expecting profits from others' efforts.
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, downloaded the software the day it was released and received ten bitcoin from its creator on 12 January 2009.
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 and trading run by code with no bank in the middle; the catch is that buggy code can be robbed, and DeFi protocols became hackers' main target in 2021 and 2022.
Q 23On Ethereum, transaction fees are priced in a unit named after what?
Gas
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
Halving comes every 210,000 blocks and cuts the reward for adding a block in two; because new supply keeps shrinking this way, the last fraction of a coin is not due until around 2140.
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 17Which company revealed in February 2021 that it had bought $1.5 billion of bitcoin?
Tesla
Tesla disclosed the $1.5 billion purchase and began taking bitcoin for its cars that March, then stopped 49 days later, citing the fossil fuels burned to produce the coins.
Q 18Which programmer, aged 19, wrote the white paper that first proposed Ethereum?
Vitalik Buterin
Vitalik Buterin wrote it in late 2013 after arguing that Bitcoin needed a fuller programming language and failing to win agreement; he took the name from a list of science-fiction elements.
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 a device that is online; in 2018 hackers drained hundreds of millions of dollars of NEM coins that the Japanese exchange Coincheck had left in one.
Q 20Which Paris-based company makes the Nano line of hardware wallets?
Ledger
Ledger's Nano wallets hold a user's keys on a chip that stays offline; a 2020 breach of its marketing database exposed customers' contact details, not their coins.
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 24What did Laszlo Hanyecz famously buy for 10,000 bitcoin in May 2010?
Two pizzas
Two pizzas from Papa John's, ordered for him by another forum user in exchange for coins then worth about $41; 22 May is now marked as Bitcoin Pizza Day.
Q 25What 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 must live on transaction fees alone.
Q 26Handling at most about seven transactions a second is known as Bitcoin's what problem?
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 second-layer networks and the 'block size wars' exist.
Q 27What 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 28Which never-built digital currency did Nick Szabo propose in 1998, a decade before Satoshi's white paper?
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 29What attack did Bitcoin Gold suffer in 2018, letting thieves reverse exchange deposits?
51% attack
A 51% attack means controlling most of a chain's hashing power, which let the thieves rewrite recent blocks and take back coins they had already paid in, costing exchanges about $18 million.
Q 30Which bitcoin-only dark-web marketplace was shut by the FBI in 2013?
Silk Road
Silk Road founder Ross Ulbricht was arrested in San Francisco in October 2013; the FBI seized the site and the US Marshals later auctioned about 30,000 of its bitcoins, and Ulbricht was sentenced to life in 2015.