Money & Economics · free reference
Part 8: What is cryptocurrency? Crypto and blockchain
What is cryptocurrency?, Blockchain basics, Stablecoins vs other coins, How crypto prices are listed, Crypto risks and scams and Crypto rules. Every fact lists its source, and you can share a link to any topic.
Go deeper: Bitcoin explained
The first cryptocurrency has its own page: the 2008 white paper section by section, who Satoshi Nakamoto is, mining, the 21 million limit, the risks and the U.S. rules.
What is cryptocurrency?
In short: Cryptocurrency is digital money that usually exists only electronically and is not backed by a government. Bitcoin was first described in a 2008 paper.[1][2]
Facts
- Cryptocurrency is a kind of digital money that usually exists only electronically.[1]6–8
- Cryptocurrency accounts are not backed by a government.[1]6–8
Go deeper: for teens and grown-ups (4)
- Cryptocurrency is kept in a digital wallet, which can be online, on a computer or on an external hard drive.[1]Teens
- Bitcoin was first described in a 2008 paper called “Bitcoin: A Peer-to-Peer Electronic Cash System,” signed with the name Satoshi Nakamoto.[2]Teens
- The paper’s goal was online payments sent straight from one person to another, without going through a bank or other financial institution.[2]Teens
- The paper defines an electronic coin as a chain of digital signatures.[2]Grown-ups
Key words in three languages
| English | Spanish | Portuguese |
|---|---|---|
| cryptocurrency[1] | criptomoneda[3] | criptomoeda[4] |
| digital wallet[1] | billetera digital[3] | not sourced yet |
Each word cites a page that uses it.
Practice this
We do not have a lesson on this yet. The facts above are the teaching here.
Sources (4)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- Satoshi Nakamoto (author), hosted at bitcoin.org · Bitcoin: A Peer-to-Peer Electronic Cash System (2008) · bitcoin.org/bitcoin.pdf (page updated 2008; checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Criptomoeda · pt.wikipedia.org/wiki/Criptomoeda (checked Oct 27, 2026)
See something we should correct about “What is cryptocurrency?”? Tell us.
Blockchain basics
In short: A blockchain is a shared digital record of transactions that is hard to change, usually with no central authority in charge.[1]
Facts
- A blockchain is a digital record book (ledger) that is shared among many computers and built so that changes are hard to make and easy to spot.[1]Teens
- Blockchains usually work without a central authority, such as a bank.[1]Teens
- They let a community of users record transactions in a ledger they all share.[1]Teens
- Bitcoin records transactions by hashing them into a growing chain of “proof-of-work” puzzles. This record is the blockchain.[2]Teens
- In Bitcoin, the longest chain serves as proof of the order in which events happened.[2]Grown-ups
Key words in three languages
| English | Spanish | Portuguese |
|---|---|---|
| blockchain[1] | cadena de bloques[3] | blockchain[4] |
| proof-of-work[2] | prueba de trabajo[5] | prova de trabalho[4] |
Each word cites a page that uses it.
Practice this
We do not have a lesson on this yet. The facts above are the teaching here.
Sources (5)
- National Institute of Standards and Technology (NIST) · Blockchain Technology Overview (NIST IR 8202) · csrc.nist.gov/pubs/ir/8202/final (page updated Oct 3, 2018; checked Oct 27, 2026)
- Satoshi Nakamoto (author), hosted at bitcoin.org · Bitcoin: A Peer-to-Peer Electronic Cash System (2008) · bitcoin.org/bitcoin.pdf (page updated 2008; checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Criptomoeda · pt.wikipedia.org/wiki/Criptomoeda (checked Oct 27, 2026)
- Wikipedia en español · Criptomoneda · es.wikipedia.org/wiki/Criptomoneda (checked Oct 27, 2026)
See something we should correct about “Blockchain basics”? Tell us.
Stablecoins vs other coins
In short: A stablecoin is a crypto token tied to a regular currency, usually the U.S. dollar, and backed by reserves. The values of most other cryptocurrencies change constantly.[1][2]
Facts
- A stablecoin is a crypto token tied one-to-one to a government currency, usually the U.S. dollar.[1]Teens
- Stablecoin issuers hold reserves, mostly cash and U.S. Treasury securities.[1]Teens
- Under the GENIUS Act, issuers must hold at least one dollar of reserves for every stablecoin they issue.[1]Grown-ups
- One risk is a “run”: if people doubt an issuer can pay back dollars, many may try to cash out at once, and the trouble could spread to the wider financial system.[1]Grown-ups
Key words in three languages
| English | Spanish | Portuguese |
|---|---|---|
| stablecoin[1] | monedas estables[3] | not sourced yet |
| cryptocurrency[2] | criptomoneda[4] | criptomoeda[5] |
Each word cites a page that uses it.
Practice this
We do not have a lesson on this yet. The facts above are the teaching here.
Sources (5)
- Federal Reserve Bank of Richmond, Econ Focus · Stablecoins and Financial Stability · richmondfed.org/publications/research/econ_focus/2025/q4_federal_reserve (page updated Dec 15, 2025; checked Oct 27, 2026)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- Wikipedia en español · Criptomoneda · es.wikipedia.org/wiki/Criptomoneda (checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Criptomoeda · pt.wikipedia.org/wiki/Criptomoeda (checked Oct 27, 2026)
See something we should correct about “Stablecoins vs other coins”? Tell us.
How crypto prices are listed
In short: Crypto price tables often show a “market cap”: the price of one unit times how many units there are. Crypto prices can swing fast, so any price is only a snapshot.[1][2]
| Coin | Price | Coins in circulation | Market cap (price × coins) | Change in 24 hours |
|---|---|---|---|---|
| Coin A | $2.00 | 1,000,000 | $2,000,000 | +5% |
| Coin B | $0.50 | 8,000,000 | $4,000,000 | −20% |
| Coin C | $1.00 | 3,000,000 | $3,000,000 | 0% |
Coin B costs the least per coin, but its market cap is the biggest, because there are more coins. A drop of 20% in one day shows how fast crypto prices can swing.
Facts
- Market capitalization (“market cap”) is the market price of one share multiplied by the number of shares.[1]Teens
- Cryptocurrency values change constantly.[3]Teens
- Crypto assets are risky and often extremely volatile: their prices can swing up and down fast.[2]Teens
- Market cap is also used for whole groups of coins. In December 2025, the Richmond Fed put the market cap of all stablecoins at about $267 billion.[4]Grown-ups
Key words in three languages
| English | Spanish | Portuguese |
|---|---|---|
| market capitalization[1] | capitalización de mercado[5] | not sourced yet |
| price[6] | precio[7] | preços[8] |
Each word cites a page that uses it.
Practice this
We do not have a lesson on this yet. The facts above are the teaching here.
Sources (8)
- U.S. Securities and Exchange Commission, Investor.gov · Market Capitalization · investor.gov/introduction-investing/investing-basics/glossary/market-capitalization (checked Oct 27, 2026)
- FINRA (Financial Industry Regulatory Authority) · Crypto Assets – Risks · finra.org/investors/investing/investment-products/crypto-assets/risks (checked Oct 27, 2026)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- Federal Reserve Bank of Richmond, Econ Focus · Stablecoins and Financial Stability · richmondfed.org/publications/research/econ_focus/2025/q4_federal_reserve (page updated Dec 15, 2025; checked Oct 27, 2026)
- Wikipedia en español · Bolsa de valores · es.wikipedia.org/wiki/Bolsa_de_valores (checked Oct 27, 2026)
- Board of Governors of the Federal Reserve System · Economy at a Glance: Inflation (PCE) · federalreserve.gov/economy-at-a-glance-inflation-pce.htm (page updated Aug 2, 2024; checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Inflação · pt.wikipedia.org/wiki/Infla%C3%A7%C3%A3o (checked Oct 27, 2026)
See something we should correct about “How crypto prices are listed”? Tell us.
Crypto risks and scams
In short: Only scammers demand payment in crypto. Crypto payments usually cannot be undone, and crypto sent to a scammer is generally gone for good.[1][2]
Facts
- If someone says you must pay them in crypto, it is a scam.[1]3–5
- Crypto payments usually cannot be reversed or undone.[1]6–8
- A promise of guaranteed money or big payouts is a sign of a scam.[1]6–8
Go deeper: for teens and grown-ups (10)
- Crypto payments do not come with legal protections like the ones credit and debit cards have.[1]Teens
- Fake investment offers are one of the top ways scammers trick people into buying crypto and sending it to them.[1]Teens
- Never mix online dating and investment advice.[1]Teens
- Scams and fraud are common with crypto, and once crypto is sent to a scammer, it is generally gone for good.[2]Teens
- Theft of crypto is a big risk.[2]Teens
- The investor protection that covers many brokerage accounts (SIPA) might not apply to crypto.[2]Grown-ups
- In a 2023 alert, the SEC warned that fraudsters use crypto’s popularity to lure people into scams.[3]Grown-ups
- The same alert said investments in crypto asset securities can be exceptionally volatile and speculative.[3]Grown-ups
- From October 2018 to September 2022, the CFPB received more than 8,300 complaints about crypto.[4]Grown-ups
- People most often reported fraud, theft, hacked accounts and scams.[4]Grown-ups
Key words in three languages
Each word cites a page that uses it.
Practice this
- Life Skills practice questions, Grade 8Questions from every Life Skills topic in the grade, with answers · freeFree
- Lesson: Digital footprint, privacy and spotting misinformationGrade 8 · full lesson with practice and a checkMembers
Members-only lessons are marked. The practice pages by grade and The Business You Build check are free.
Sources (7)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- FINRA (Financial Industry Regulatory Authority) · Crypto Assets – Risks · finra.org/investors/investing/investment-products/crypto-assets/risks (checked Oct 27, 2026)
- U.S. Securities and Exchange Commission, Investor.gov · Exercise Caution with Crypto Asset Securities: Investor Alert · investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-alerts/crypto-asset-securities (page updated Mar 23, 2023; checked Oct 27, 2026)
- Consumer Financial Protection Bureau · CFPB Publishes New Bulletin Analyzing Rise in Crypto-Asset Complaints · consumerfinance.gov/about-us/newsroom/cfpb-publishes-new-bulletin-analyzing-rise-in-crypto-asset-complaints (page updated Nov 10, 2022; checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Cartão de crédito · pt.wikipedia.org/wiki/Cart%C3%A3o_de_cr%C3%A9dito (checked Oct 27, 2026)
- Wikipédia em português · Criptomoeda · pt.wikipedia.org/wiki/Criptomoeda (checked Oct 27, 2026)
See something we should correct about “Crypto risks and scams”? Tell us.
Crypto rules
In short: Crypto oversight is an ongoing area of rule-making. The CFTC has called Bitcoin a commodity, and a 2025 federal law, the GENIUS Act, set rules for payment stablecoins.[1][2][3]
Facts
- The GENIUS Act, a federal law setting rules for payment stablecoins, became Public Law 119-27 on July 18, 2025.[2]Teens
- Registration of crypto assets, and of the companies that deal in them, is limited, so you might deal with companies that are not registered.[3]Teens
- In 2017, the CFTC said Bitcoin and other virtual currencies have been found to be commodities under the Commodity Exchange Act.[1]Grown-ups
- The CFTC can act against fraud and manipulation in cash markets for virtual currencies, but its oversight of those cash markets is limited.[1]Grown-ups
- In its 2023 alert, the SEC warned that some people offering crypto investments or services may not be following the law.[4]Grown-ups
Key words in three languages
| English | Spanish | Portuguese |
|---|---|---|
| cryptocurrency[5] | criptomoneda[6] | criptomoeda[7] |
| stablecoin[8] | monedas estables[9] | not sourced yet |
Each word cites a page that uses it.
Practice this
- Business practice questions, Grade 8Questions from every Business topic in the grade, with answers · freeFree
- Lesson: Taxes and regulationGrade 8 · full lesson with practice and a checkMembers
Each word cites a page that uses it.
Sources (9)
- Commodity Futures Trading Commission · CFTC Launches Virtual Currency Resource Web Page (Release 7665-17) · cftc.gov/PressRoom/PressReleases/7665-17 (page updated Dec 15, 2017; checked Oct 27, 2026)
- U.S. Government Publishing Office, govinfo · Public Law 119-27: Guiding and Establishing National Innovation for U.S. Stablecoins Act (GENIUS Act) · govinfo.gov/app/details/PLAW-119publ27 (page updated Jul 18, 2025; checked Oct 27, 2026)
- FINRA (Financial Industry Regulatory Authority) · Crypto Assets – Risks · finra.org/investors/investing/investment-products/crypto-assets/risks (checked Oct 27, 2026)
- U.S. Securities and Exchange Commission, Investor.gov · Exercise Caution with Crypto Asset Securities: Investor Alert · investor.gov/introduction-investing/general-resources/news-alerts/alerts-bulletins/investor-alerts/crypto-asset-securities (page updated Mar 23, 2023; checked Oct 27, 2026)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- Consumer Financial Protection Bureau · Glossary of English-Spanish financial terms (Spanish style guide and glossary) · files.consumerfinance.gov/f/documents/cfpb_adult-fin-ed_spanish-style-guide-glossary.pdf (checked Oct 27, 2026)
- Wikipédia em português · Criptomoeda · pt.wikipedia.org/wiki/Criptomoeda (checked Oct 27, 2026)
- Federal Reserve Bank of Richmond, Econ Focus · Stablecoins and Financial Stability · richmondfed.org/publications/research/econ_focus/2025/q4_federal_reserve (page updated Dec 15, 2025; checked Oct 27, 2026)
- Wikipedia en español · Criptomoneda · es.wikipedia.org/wiki/Criptomoneda (checked Oct 27, 2026)
See something we should correct about “Crypto rules”? Tell us.
Questions parents ask
Is Bitcoin a cryptocurrency?
Bitcoin is a cryptocurrency, a kind of digital money that usually exists only electronically[1]. It was first described in a 2008 paper signed Satoshi Nakamoto, which aimed for online payments sent directly from one person to another without a bank[2]. Bitcoin records transactions in a growing chain of blocks, the blockchain[2]. Crypto accounts are not backed by a government[1], and crypto values change constantly[1].
Read more: Bitcoin explained: the white paper and how it works
Can a teenager buy crypto?
This page does not give a how-to. What regulators stress for anyone thinking about crypto: values change constantly[1], crypto payments usually cannot be reversed[1], scams are common and crypto sent to a scammer is generally gone for good[3], and only scammers demand payment in crypto[1]. A teen thinking about crypto should talk with a parent or guardian first.
What is a stablecoin, and how does it work?
A stablecoin is a crypto token tied one-to-one to a government currency, usually the U.S. dollar[4]. Issuers hold reserves, mostly cash and U.S. Treasury securities[4], and under the GENIUS Act they must hold at least one dollar of reserves for every stablecoin they issue[4]. One risk is a run, when many people try to cash out at once[4].
What is a crypto “market cap”?
Market capitalization is a market price multiplied by how many units there are[5]. For a coin, that means the price of one coin times the number of coins. Crypto prices are often extremely volatile[3], so market caps change all the time. The table in this topic uses made-up coins to show the math.
Who regulates crypto?
Crypto oversight is shared among agencies and is an ongoing area of rule-making. The CFTC has said Bitcoin and other virtual currencies are commodities[6], and it can act against fraud and manipulation in those cash markets[6]. The GENIUS Act, which became law on July 18, 2025, set federal rules for payment stablecoins[7]. FINRA notes that registration of crypto assets, and of the companies that deal in them, is limited[3].
Is crypto safe for teens?
Crypto assets are risky and often extremely volatile: their prices can swing up and down fast.[3] Crypto payments usually cannot be reversed or undone.[1] Crypto payments do not come with legal protections like the ones credit and debit cards have.[1] If someone says you must pay them in crypto, it is a scam.[1]
Sources for these answers (7)
- Federal Trade Commission, Consumer Advice · What To Know About Cryptocurrency and Scams · consumer.ftc.gov/articles/what-know-about-cryptocurrency-and-scams (checked Oct 27, 2026)
- Satoshi Nakamoto (author), hosted at bitcoin.org · Bitcoin: A Peer-to-Peer Electronic Cash System (2008) · bitcoin.org/bitcoin.pdf (page updated 2008; checked Oct 27, 2026)
- FINRA (Financial Industry Regulatory Authority) · Crypto Assets – Risks · finra.org/investors/investing/investment-products/crypto-assets/risks (checked Oct 27, 2026)
- Federal Reserve Bank of Richmond, Econ Focus · Stablecoins and Financial Stability · richmondfed.org/publications/research/econ_focus/2025/q4_federal_reserve (page updated Dec 15, 2025; checked Oct 27, 2026)
- U.S. Securities and Exchange Commission, Investor.gov · Market Capitalization · investor.gov/introduction-investing/investing-basics/glossary/market-capitalization (checked Oct 27, 2026)
- Commodity Futures Trading Commission · CFTC Launches Virtual Currency Resource Web Page (Release 7665-17) · cftc.gov/PressRoom/PressReleases/7665-17 (page updated Dec 15, 2017; checked Oct 27, 2026)
- U.S. Government Publishing Office, govinfo · Public Law 119-27: Guiding and Establishing National Innovation for U.S. Stablecoins Act (GENIUS Act) · govinfo.gov/app/details/PLAW-119publ27 (page updated Jul 18, 2025; checked Oct 27, 2026)