Bitcoin 101: What It Is and How It Works

What is Bitcoin?

Bitcoin is a digital currency that operates without a central authority — no bank, no government, no company runs it. It was created in 2008 by a pseudonymous person or group called Satoshi Nakamoto, who published a nine-page whitepaper laying out a system for electronic cash that could be sent between people without a trusted middleman.

The core problem it solved is the double-spend: with ordinary digital files you can copy and paste endlessly, so how do you stop someone spending the same digital money twice? Bitcoin solved this by having all transactions recorded on a shared ledger — the blockchain — that thousands of independent computers maintain and agree on simultaneously.

The blockchain

Every Bitcoin transaction is broadcast to the network and eventually bundled into a block. Each block is cryptographically linked to the one before it, forming a chain back to the very first block mined in January 2009. Altering any past transaction would require rewriting that block and every subsequent one faster than the rest of the network combined — computationally impractical once a few blocks have passed.

This is what makes the blockchain trustworthy without a central authority: no single party keeps the books, and the rules are enforced by the network itself. See the blockchain glossary entry for a fuller explanation.

Mining and proof of work

New Bitcoin transactions are validated and recorded by participants called miners. Miners run specialised computers that race to solve a computationally hard puzzle. The winner adds the next block and receives a reward of newly created bitcoin. This process is called proof of work because the only way to find the solution is brute-force computation — real, measurable effort that makes cheating expensive.

Mining is also how new bitcoin enters circulation. As of 2024, miners earn 3.125 BTC per block. That reward will fall again at the next halving, and so on until all 21 million coins are eventually mined (expected around 2140). After that, miners are compensated only through transaction fees.

The 21-million cap and halvings

Bitcoin has a hard-coded maximum supply of 21 million coins. No more can ever be created — the rule is written into the software every Bitcoin node runs. To reach that cap slowly and predictably, Bitcoin undergoes a halving roughly every four years: the block reward is cut in half, slowing the rate of new supply.

This fixed, diminishing issuance is often contrasted with fiat currencies, where central banks can expand supply at will. The mechanism means Bitcoin is disinflationary by design: the growth in total supply decelerates at each halving and eventually stops entirely.

Wallets and private keys

To hold or spend Bitcoin you need a wallet. Despite the name, a wallet does not store coins — it stores the private key that proves you own a particular address on the blockchain. Whoever controls the private key controls the funds, with no recourse if it is lost or stolen.

Wallets come in two broad types. Hot wallets stay connected to the internet and are convenient for everyday spending. Cold wallets keep keys offline — on a hardware device or paper — and are suited to long-term storage. The tradeoff is always convenience versus security.

The phrase "not your keys, not your coins" captures the self-custody philosophy: leaving bitcoin on an exchange means trusting that company with your private key. If the exchange is hacked or collapses, recovery is not guaranteed.

Volatility and risk

Bitcoin’s price has historically swung by large amounts in both directions. Multiple 50–80% drawdowns have occurred, each followed eventually by new highs — though past performance says nothing about whether that pattern will continue. A position you cannot afford to hold through a severe downturn is too large.

Bitcoin is not a savings account, a bond, or a stock with underlying earnings. It is a digital asset whose value rests on network adoption, scarcity and sentiment. Understand what you are holding before you hold it.

Where to learn more on TheWeal

• Blockchain — how the ledger works in detail
• Halving — the supply schedule explained
• Private key — why it is the most important thing to protect
• Proof of work — how mining secures the network
• Bitcoin live price page — current price, predictions and metrics
• Our methodology — how TheWeal builds its price scenarios

Educational content only. Not financial advice. Nothing here is a recommendation to buy, sell or hold any asset. Prices are volatile; only risk what you can afford to lose entirely.