What is Bitcoin in simple terms?

Bitcoin is a digital currency that operates without any central authority like a bank or government. It runs on a decentralized network of computers worldwide. People can send Bitcoin directly to each other over the internet, and every transaction is recorded on a public ledger called the blockchain.

How does Bitcoin make money?

Bitcoin itself does not generate revenue like a company. Its value comes from supply and demand. There will only ever be 21 million Bitcoins, and as demand increases while supply remains fixed, the price can rise. People profit from Bitcoin by buying it at a lower price and selling at a higher one, though the price can also fall significantly.

The Bitcoin network itself has never been hacked in its 17-year history. However, exchanges and wallets that hold Bitcoin have been hacked. The main risks are losing access to your private keys, sending Bitcoin to the wrong address, or having your exchange account compromised. Using a hardware wallet and following security best practices significantly reduces these risks.

Bitcoin was created by a person or group using the pseudonym Satoshi Nakamoto. The Bitcoin whitepaper was published in October 2008, and the network launched in January 2009. Satoshi's true identity remains unknown. They stopped communicating publicly in 2011 and have not moved any of their estimated 1 million Bitcoin since.

How many Bitcoins are there?

The maximum supply of Bitcoin is hard-capped at 21 million coins. As of 2026, approximately 19.8 million have been mined. New Bitcoins are created through mining at a decreasing rate -- the reward halves roughly every four years. The last Bitcoin is projected to be mined around the year 2140.

Can Bitcoin be hacked?

The Bitcoin blockchain itself is extraordinarily difficult to hack. An attacker would need to control more than 50% of the entire network's computing power, which currently costs billions of dollars and is practically infeasible. However, individual wallets, exchanges, and bridge protocols can be hacked if they have security vulnerabilities.

What Is Bitcoin? How It Works in Simple Terms

The first cryptocurrency

Bitcoin launched on January 3, 2009, when a pseudonymous person or group called Satoshi Nakamoto mined the first block -- known as the "genesis block." The timing was not accidental. The 2008 financial crisis had exposed deep fragility in the banking system, and Satoshi embedded a newspaper headline in that first block: "Chancellor on brink of second bailout for banks."

Bitcoin was designed as an alternative: a form of money that no bank, government, or company could control. Seventeen years later, Satoshi's identity remains unknown, and Bitcoin has grown into an asset class worth over a trillion dollars.

What Bitcoin actually is

Bitcoin is a decentralized digital currency. That phrase contains three important ideas:

Decentralized. No single entity controls Bitcoin. The network is maintained by thousands of computers (nodes) spread across the globe. No one can unilaterally change the rules, freeze accounts, or inflate the supply.
Digital. Bitcoin exists only as entries on a digital ledger. There are no physical coins. Your "balance" is simply the sum of all transactions sent to your address minus all transactions sent from it.
Currency. Bitcoin can be sent from one person to another without an intermediary. Transactions are irreversible and do not require permission from any authority.

How Bitcoin works

When you send Bitcoin to someone, your transaction is broadcast to the network. Here is what happens next:

Transaction broadcast. Your wallet signs the transaction with your private key, proving you own the BTC, and broadcasts it to the network.
Mempool. The transaction enters a waiting area called the mempool. Miners select transactions from the mempool to include in the next block, generally prioritizing those with higher fees.
Mining. Miners compete to solve a computationally difficult puzzle. The first to solve it earns the right to add the next block of transactions to the chain and receives a reward in newly created BTC.
Confirmation. Once your transaction is included in a block, it has one confirmation. Each subsequent block added on top provides additional confirmation, making the transaction progressively harder to reverse. Most recipients consider a transaction final after six confirmations (roughly one hour).

Key properties

Fixed supply

There will only ever be 21 million Bitcoin. This cap is enforced by the protocol's code and cannot be changed without consensus from the entire network. Approximately 19.8 million have been mined so far.

Permissionless

Anyone with an internet connection can use Bitcoin. There is no application process, no credit check, no minimum balance. You download a wallet and you are on the network.

Censorship-resistant

No single entity can block a Bitcoin transaction. As long as you pay the network fee, your transaction will eventually be processed by some miner somewhere in the world.

Pseudonymous

Bitcoin addresses are not tied to real-world identities by default. However, Bitcoin is not anonymous. Every transaction is publicly visible on the blockchain, and sophisticated analysis can often link addresses to identities.

Mining and Proof of Work

Bitcoin uses a consensus mechanism called Proof of Work (PoW). Miners deploy specialized hardware (ASICs) to repeatedly compute cryptographic hashes, racing to find one that meets the network's difficulty target. This process consumes significant electricity -- roughly comparable to the annual energy usage of a mid-sized country.

The energy consumption is controversial but intentional. It is the cost of securing the network without a central authority. The more energy spent on mining, the more expensive it becomes for any attacker to rewrite the blockchain's history. This is what makes Bitcoin's transaction record practically immutable.

The halving

Every 210,000 blocks (approximately every four years), the mining reward is cut in half. When Bitcoin launched, miners earned 50 BTC per block. After the first halving in 2012, it dropped to 25. It halved again to 12.5 in 2016, to 6.25 in 2020, and to 3.125 in 2024. The next halving is expected around 2028.

Halvings reduce the rate of new supply entering the market. Historically, Bitcoin's price has risen substantially in the 12 to 18 months following each halving, though past performance is not a reliable indicator of future results. The halving schedule ensures that the last Bitcoin will not be mined until approximately 2140.

Bitcoin as store of value

The "digital gold" thesis argues that Bitcoin's fixed supply, durability, portability, and resistance to seizure make it a superior store of value compared to gold. Proponents point to Bitcoin's outperformance of every other asset class over the past decade, its increasing institutional adoption (Bitcoin ETFs, corporate treasury holdings), and its independence from any single government's monetary policy.

Critics counter that Bitcoin is far too volatile to serve as a reliable store of value, that it produces no cash flow, and that its value rests entirely on the assumption that future buyers will pay more than past buyers did. Both sides have reasonable arguments, and the debate is far from settled. For a deeper look at the risks, see our guide on whether crypto can go to zero.

Bitcoin vs. Ethereum

Property	Bitcoin (BTC)	Ethereum (ETH)
Primary purpose	Store of value, payments	Programmable platform
Supply	Hard cap: 21 million	No hard cap (but can be deflationary)
Consensus	Proof of Work	Proof of Stake
Smart contracts	Very limited (Script)	Fully programmable (Solidity)
Block time	~10 minutes	~12 seconds
Ecosystem	Primarily a monetary asset	DeFi, NFTs, DAOs, Layer 2s

Bitcoin and Ethereum are not competitors in the way that Ford and Toyota are. They serve fundamentally different purposes, and most serious crypto portfolios include both.

Bitcoin in DeFi

Bitcoin's blockchain has limited programmability, which means DeFi protocols cannot run directly on it the way they do on Ethereum. To use BTC in DeFi, holders bridge it to Ethereum as wrapped tokens -- most commonly WBTC (Wrapped Bitcoin) or cbBTC (Coinbase Wrapped BTC). These are ERC-20 tokens on Ethereum, each backed 1:1 by real BTC held in custody. You can learn more about how these work in our guide to token types.

The Lightning Network

The Lightning Network is a Layer 2 protocol built on top of Bitcoin that enables fast, cheap payments. Instead of recording every transaction on the main blockchain, Lightning opens payment channels between users and settles the net result on-chain. This allows for near-instant transactions at fractions of a cent -- making Bitcoin practical for everyday purchases rather than just large transfers.

Common misconceptions

"Bitcoin is anonymous." It is pseudonymous, not anonymous. Every transaction is permanently recorded on a public blockchain. Chain analysis firms routinely link Bitcoin addresses to real identities. For most users, Bitcoin offers less privacy than cash.
"Bitcoin is only used by criminals." Blockchain analytics firm Chainalysis estimates that illicit activity accounts for less than 1% of Bitcoin transaction volume. The transparency of the blockchain actually makes it a poor choice for crime -- the FBI has seized billions in Bitcoin from criminal operations precisely because every transaction is traceable.
"A government can shut down Bitcoin." No single government can shut down a decentralized global network. China banned Bitcoin mining in 2021; miners simply relocated to other countries, and the network recovered within months. Short of a coordinated global shutdown of the internet, Bitcoin cannot be stopped.

Tracking your Bitcoin

Whether you hold BTC on the Bitcoin network, wrapped BTC on Ethereum, or BTC across multiple wallets and chains, keeping track of your actual exposure matters. Understanding your holdings in context -- alongside the rest of your portfolio -- is fundamental to making informed decisions about risk management. For practical guidance on managing your crypto safely, see our guide to crypto wallets and blockchain basics.

If you are wondering whether now is the right time to buy, our guide on whether to buy Bitcoin walks through the key considerations without making predictions.

Track your Bitcoin alongside all your other crypto -- across every network, one clear view.

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