Bitcoin is the first and largest cryptocurrency — the asset that started the entire industry. Over 15 years after its creation, Bitcoin remains the dominant digital asset by market cap and is increasingly held by institutions, governments, and retail investors worldwide.
Here’s what Bitcoin is, how it works, and why it matters.
What is Bitcoin?
Bitcoin (ticker: BTC) is a decentralised digital currency. It exists entirely on the internet — there are no physical coins or notes — and it operates without banks, governments, or central authorities.
Key properties:
Bitcoin was created in 2008 by an anonymous person or group using the pseudonym Satoshi Nakamoto, who published the Bitcoin whitepaper titled “Bitcoin: A Peer-to-Peer Electronic Cash System.” Nakamoto launched the network in January 2009 and then disappeared, leaving the project to the community.
No one knows who Satoshi Nakamoto is. Their identity remains one of the great mysteries of the internet age.
How Does Bitcoin Work?
The Blockchain
Bitcoin runs on a blockchain — a distributed ledger maintained by thousands of computers (nodes) worldwide. Every Bitcoin transaction is recorded on this ledger, visible to anyone.
A “block” is a bundle of recent transactions. Each block is mathematically linked to the previous one, forming a chain. Altering any past block would require recalculating all subsequent blocks — computationally impossible without controlling 51% of the network’s power.
This makes Bitcoin:
Bitcoin Mining
New Bitcoin enters circulation through mining — a process where computers compete to solve complex mathematical puzzles. The first to solve the puzzle gets to add the next block to the blockchain and receives a block reward of newly created Bitcoin, plus transaction fees.
Mining serves two purposes:
Mining is energy-intensive. Critics argue this is wasteful; proponents argue it provides robust security and uses electricity that would otherwise be wasted, or is increasingly renewable.
Bitcoin Halving
Every 210,000 blocks (approximately every 4 years), the Bitcoin block reward is cut in half. This is called the halving.
| Halving | Date | Block Reward |
|---|---|---|
| Genesis | 2009 | 50 BTC |
| 1st Halving | 2012 | 25 BTC |
| 2nd Halving | 2016 | 12.5 BTC |
| 3rd Halving | 2020 | 6.25 BTC |
| 4th Halving | 2024 | 3.125 BTC |
| 5th Halving | ~2028 | 1.5625 BTC |
The halvings reduce the rate at which new Bitcoin is created, making Bitcoin increasingly scarce over time. This built-in scarcity is a key feature of Bitcoin’s monetary design. The final Bitcoin will be mined around the year 2140.
Sending and Receiving Bitcoin
A Bitcoin address is like a bank account number — a string of characters (e.g., bc1qxy2kgdygjrsqtzq2n0yrf2493p83kkfjhx0wlh) that you share to receive funds.
Each address is controlled by a private key — a long cryptographic string that proves ownership. Whoever controls the private key controls the Bitcoin at that address.
Transactions are broadcast to the network, picked up by miners, and confirmed when included in a block. A transaction with 6 confirmations (6 blocks built on top of the block containing it) is considered irreversible.
Why Does Bitcoin Have Value?
Bitcoin’s value comes from several properties working together:
Scarcity: 21 million BTC, no more ever. This is mathematically guaranteed by the protocol.
Security: Bitcoin has never been hacked at the protocol level. Its security has been tested continuously since 2009.
Decentralisation: No company, government, or individual can seize or freeze Bitcoin held in self-custody.
Network effects: Bitcoin has the largest user base, most liquidity, and most infrastructure of any cryptocurrency. This makes it more useful and trusted.
Portability: 1 BTC can be sent anywhere in the world in minutes. Gold cannot do this.
Verifiability: Anyone with a computer can verify that a Bitcoin transaction is valid. You don’t need to trust anyone.
Censorship resistance: No authority can block a valid Bitcoin transaction.
Bitcoin’s comparison to gold is common — both are scarce, durable, and require no counterparty to hold. Bitcoin adds: verifiability, portability, and digital transferability.
Bitcoin vs Other Cryptocurrencies
Bitcoin is unique compared to other cryptocurrencies:
| Feature | Bitcoin | Ethereum | XRP | Solana |
|---|---|---|---|---|
| Primary purpose | Store of value / money | Programmable platform | Payments | Fast dApps |
| Smart contracts | Limited | Core feature | Limited | Core feature |
| Consensus | Proof of Work | Proof of Stake | Federated | Proof of History |
| Supply | 21M cap | No hard cap | 100B pre-mined | ~580M |
| Decentralisation | Highest | High | Moderate | Moderate |
| Track record | 15+ years | 10+ years | 12+ years | 5+ years |
Bitcoin prioritises security and decentralisation above all else. This means slower transactions and fewer features than newer blockchains — a deliberate design choice.
Bitcoin as an Investment
Bitcoin has been one of the best-performing assets of the past decade. However, it has also experienced significant crashes:
- 2011: -94%
- 2013–2015: -87%
- 2017–2018: -84%
- 2021–2022: -77%
Every major crash was followed by Bitcoin recovering to new all-time highs — but there is no guarantee this pattern continues.
Institutional adoption has accelerated:
- Bitcoin ETFs approved in the US (January 2024) — opened Bitcoin exposure to traditional investors
- MicroStrategy, Tesla, and other public companies hold Bitcoin on their balance sheets
- Several nation-states hold or have discussed holding Bitcoin reserves
- Traditional asset managers (BlackRock, Fidelity, Vanguard) now offer Bitcoin products
Not investment advice: Bitcoin is a highly volatile asset. Many investors hold it as a small percentage of a diversified portfolio. Others hold only Bitcoin. Your allocation should reflect your risk tolerance and financial situation.
How to Buy Bitcoin
How to Store Bitcoin
Exchange wallet (custodial): Convenient, but the exchange controls your keys. Suitable for trading or small amounts.
Software wallet: Self-custody on your phone or computer. Good options: Electrum (Bitcoin-only, desktop), BlueWallet (mobile, supports Lightning Network).
Hardware wallet (recommended for significant amounts): Ledger or Trezor store your private keys offline, completely isolated from the internet. “Not your keys, not your coins.”
Bitcoin and Tax (UK)
Bitcoin is treated as a capital asset by HMRC. Capital Gains Tax applies when you:
- Sell BTC for GBP
- Swap BTC for another crypto
- Spend BTC on goods or services
Receiving Bitcoin as income (mining, salary) attracts Income Tax. Buying and holding has no immediate tax consequence. Keep records of every transaction.
Common Bitcoin Questions
Can Bitcoin be hacked?
Bitcoin’s core protocol has never been hacked. Individual exchanges and wallets have been hacked, but the Bitcoin blockchain itself has a perfect security record since 2009.
What is a Bitcoin wallet?
A wallet is software that stores your private keys and allows you to send/receive Bitcoin. It doesn’t actually “contain” Bitcoin — Bitcoin exists on the blockchain, and the wallet just holds the keys to access it.
Is Bitcoin anonymous?
Bitcoin is pseudonymous, not anonymous. All transactions are public on the blockchain. Wallet addresses don’t have names attached, but with enough analysis, transactions can be traced. For privacy, additional tools (Wasabi Wallet, CoinJoin) are needed.
What is the Lightning Network?
The Lightning Network is a Layer 2 solution for Bitcoin that enables instant, near-free microtransactions. Channels are opened on the main Bitcoin blockchain and can process thousands of small transactions off-chain before settling.
Can governments ban Bitcoin?
Governments can ban exchanges and on-ramps (buying/selling). They cannot destroy the Bitcoin network itself — it runs on thousands of computers worldwide. China has banned Bitcoin exchanges multiple times; Chinese Bitcoin holders continue to hold and transact.
What is a Bitcoin node?
A node is a computer that runs the Bitcoin software and maintains a full copy of the blockchain. Running a node allows you to verify transactions yourself without trusting anyone. A basic computer can run a Bitcoin node.
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