How Does Cryptocurrency Work?

Cryptocurrency is digital money that exists only as entries in a shared public record called a blockchain, rather than as bills in your wallet or numbers in one bank's database.

Instead of a bank deciding who owns what, thousands of computers around the world each keep a copy of that record and agree on every update by following the same software rules.

Those rules rely on cryptography, a branch of math that scrambles information so only someone holding the right digital key can unlock or approve it.

You control your coins with two linked codes: a public address, which works like an account number anyone can send money to, and a private key, which works like a password that proves the coins are yours.

Picture sending $50 worth of bitcoin to a friend to cover your half of a concert ticket.

Your wallet app uses your private key to sign the payment, creating a digital stamp that proves you approved it without revealing the key itself.

Computers on the network check the shared record to confirm you actually own that $50 in bitcoin and have not already spent it elsewhere.

Your payment is then bundled with a few thousand others into a batch called a block, and a new block joins Bitcoin's record roughly every 10 minutes.

Your friend receives the bitcoin without a bank, a business day, or a border getting involved, though you typically pay a small network fee that rises when the network is busy.

That ability to hold and move value without anyone's permission is the core appeal, and it is why a technology that began as an online experiment now sits inside funds run by BlackRock and Fidelity.

What Is a Blockchain?

A blockchain is a ledger, or running list of transactions, split into blocks that are chained together in order, with a copy held by every computer on the network.

Think of it as a notebook that thousands of strangers each keep an identical copy of, where every new page includes a unique fingerprint of the page before it.

If someone secretly changed an old entry to give themselves extra coins, that page's fingerprint would change, breaking the link to every later page, and every other copy would reject the edit.

That shared, tamper-resistant record is what lets crypto work without a bank in the middle: the network itself keeps score.

How Are New Coins Created?

New coins are paid out as a reward to the computers that verify transactions and add new blocks, and most networks use one of two systems to decide who earns it.

Proof of Work

In proof of work, the system Bitcoin uses, computers called miners race to solve a math puzzle, and the winner adds the next block and collects newly created bitcoin plus transaction fees.

The reward has been 3.125 bitcoin per block since the April 2024 halving, a scheduled cut that happens roughly every four years, and the total supply can never exceed 21 million coins.

Proof of Stake

In proof of stake, validators lock up, or stake, their own coins as a security deposit for the chance to confirm blocks and earn rewards, and they can lose part of that deposit if they cheat.

Ethereum switched to this system in September 2022 and cut its energy use by an estimated 99.95%, since it no longer needs warehouses of power-hungry machines.

The Main Types of Cryptocurrency

Bitcoin

Bitcoin, launched in 2009 by a person or group using the name Satoshi Nakamoto, is the first and largest cryptocurrency.

Most people hold it as a store of value, meaning something kept to preserve or grow wealth over time, rather than to buy coffee.

Ethereum

Ethereum is a blockchain that runs smart contracts, which are programs that automatically carry out an agreement once set conditions are met.

Its coin, ether, pays the fees for running those programs, which power apps for lending, trading, and digital collectibles.

Stablecoins

Stablecoins are tokens designed to hold a steady value, usually $1, by keeping reserves, mostly cash and Treasury bills, which are short-term loans to the U.S. government, behind each coin.

Unlike bitcoin, they are issued by companies such as Circle and Tether, which can freeze the tokens sitting in a specific address.

Meme Coins

Meme coins like Dogecoin started as internet jokes and have little purpose beyond online hype.

Their prices can double or collapse in a single day, which makes them closer to a lottery ticket than an investment.

Why Does Cryptocurrency Have Value?

A cryptocurrency is worth whatever buyers will pay for it, much like a rare baseball card or an ounce of gold.

Bitcoin's fans point to its fixed supply, its independence from any government, and its ability to be sent anywhere at any hour, and those traits keep demand alive.

The honest tradeoff is that, unlike a stock, most crypto produces no profits and pays no dividends, so its price rests almost entirely on what the next buyer believes it is worth.

That makes prices swing hard: bitcoin hit a record above $126,000 in October 2025, then slid below $60,000 by late June 2026, losing more than half its value in about eight months.

It has since climbed back to the low $80,000s, but swings like that are the reason to size any purchase so a 50% drop would sting without touching your rent, emergency fund, or retirement savings.

Is Cryptocurrency Anonymous?

Many people assume crypto is untraceable, but most blockchains are completely public, so anyone can look up every transaction an address has ever made.

What crypto offers is pseudonymity: addresses are strings of characters rather than names, but once one is tied to a real person, often through an exchange that verified their ID, their full history can be traced.

That transparency is how investigators follow stolen funds, and it also means anyone who learns your address can see your balance and past payments.

How Do You Buy and Store Cryptocurrency?

Most beginners buy through an exchange, a company that lets you trade dollars for digital coins much like a brokerage lets you trade dollars for stocks.

Opening an account requires a photo ID and your Social Security number, since U.S. exchanges must verify their customers, and you fund it by linking a bank account or debit card.

You never need to buy a whole coin, because bitcoin can be split into units as small as one hundred-millionth of a coin, so $25 buys exactly $25 worth.

If you want to start small and own the coins directly, Gemini lets you buy bitcoin, ether, and dozens of other cryptocurrencies in small dollar amounts, and you can move them to your own wallet later.

Once you buy, you also choose where your crypto lives, and that choice matters as much as what you bought.

Custodial Accounts

When you leave coins on an exchange, the exchange holds the private keys for you, which is convenient and means a forgotten password can be reset.

The tradeoff is that your access depends on that company staying secure and in business.

Self-Custody Wallets

A self-custody wallet, either a phone app or a hardware device about the size of a thumb drive, keeps the private keys in your hands so no company can freeze or lose your coins.

The catch is total responsibility: if you lose your recovery phrase, the list of 12 or 24 words that backs up your keys, no one can restore your coins.

Spot Bitcoin ETFs

A spot bitcoin exchange-traded fund, or ETF, holds actual bitcoin and trades like a stock in a regular brokerage account, an option the SEC approved in January 2024.

You get bitcoin's price movements for a small annual fee, but you cannot send the coins to anyone or use them on a blockchain.

What Are the Biggest Risks?

Beyond price swings, two threats cause most of the money people lose in crypto.

Exchange Hacks and Failures

Crypto held at an exchange is not covered by FDIC insurance, the federal program that protects bank deposits up to $250,000.

In September 2026, hackers took more than $350 million from the exchange Bitget, which paused customer withdrawals for days even though it said customer balances were fully covered.

Scams

Because crypto payments cannot be reversed, Americans reported more than $11 billion in crypto-related fraud losses to the FBI in 2025, with fake investment pitches driving the largest share.

Turn on two-factor authentication, a second login step such as a code texted to your phone, and treat anyone who asks for your recovery phrase as a scammer.

How Is Cryptocurrency Taxed?

The IRS treats cryptocurrency as property, not currency, so it is taxed much like a stock.

Selling crypto for dollars, trading one coin for another, and spending it on a purchase are all taxable events, meaning you owe tax on any gain since you bought it.

If you buy $1,000 of bitcoin, it grows to $1,500, and you spend all of it on a laptop, you owe tax on the $500 gain even though no dollars ever reached your bank account.

Starting with 2025 transactions, U.S. exchanges send both you and the IRS a Form 1099-DA reporting what you sold.

Simply buying crypto with dollars and holding it is not taxable, so the record that matters most is what you paid for each purchase, since that number sets your gain or loss when you sell.