In 2010 a programmer named Laszlo Hanyecz made the most famous purchase in crypto history.

He paid 10,000 Bitcoin for two pizzas.

At the time those Bitcoin were worth roughly 41 dollars. At Bitcoin's all time high of approximately $126,000 reached in October 2025 those same 10,000 Bitcoin were worth over one billion dollars. That is the most expensive pizza in human history.

Laszlo knew exactly what he was doing — he was one of the earliest Bitcoin miners and he had earned those coins by dedicating his computer to securing the network.

Most people have heard of crypto mining. Far fewer actually understand what it is, why it exists and why it consumes so much energy. By the end of this article you will understand all three.

Why Mining Exists

Before understanding what mining is it helps to understand the problem it solves.

When you send money through a bank the bank keeps a record of the transaction. They update their database, deduct money from your account and add it to the recipient's account. The bank is the trusted authority that ensures the transaction is legitimate and that you are not spending money you do not have.

Bitcoin has no bank. No central authority. No company keeping the records. So how does the network ensure that transactions are legitimate? How does it prevent someone from spending the same Bitcoin twice — sending it to two different people simultaneously and trying to get away with it?

The answer is mining.

Mining is the process by which transactions are verified and added permanently to the blockchain. Miners are the people — and the computers — doing that verification work. And the reward for doing that work honestly is newly created Bitcoin.

The Global Puzzle Competition

Imagine a massive global competition happening every ten minutes.

Thousands of computers around the world are all trying to solve the same incredibly difficult puzzle simultaneously. The puzzle cannot be solved through logic or creativity — the only way to find the answer is to try billions of random combinations until one works. The computer that finds the solution first wins the right to add the next block of transactions to the blockchain and receives a reward of newly created Bitcoin.

Then the puzzle resets and the competition begins again.

That competition — happening continuously, simultaneously, across thousands of computers in dozens of countries — is Bitcoin mining.

The puzzle miners are solving is called a hash function. Without getting too technical a hash function takes any input and produces a fixed length output called a hash. The challenge is to find an input that produces a hash meeting specific criteria — starting with a certain number of zeros for example. Because a hash function is a one way street — you can easily turn an input into a hash but you cannot reverse a hash back into its original input — the only way to find such an input is to try random combinations over and over at incredible speed until one works.

A modern mining computer can attempt billions of these combinations per second. The more attempts per second a miner can make the better their chances of finding the solution before anyone else.

Why it Requires So Much Energy

This is the question most people ask about mining and it deserves a direct honest answer.

Mining requires enormous amounts of energy because the puzzle is deliberately designed to be difficult. That difficulty is not a flaw — it is the entire point.

Making the puzzle easy to solve would make the network cheap and easy to attack. If you could solve the puzzle with a basic laptop you could flood the network with fraudulent transactions at minimal cost. The energy requirement is what makes attacking Bitcoin extraordinarily expensive — you would need to control more computing power than the entire rest of the network combined and sustain that for long enough to rewrite the blockchain. The cost of doing so is so astronomical that it has never been successfully attempted.

Think of the energy consumption as Bitcoin's security budget. The more energy going into mining the more secure the network becomes. Every kilowatt hour of electricity being consumed by miners around the world is a kilowatt hour making Bitcoin harder to attack.

That said the environmental concerns around Bitcoin's energy consumption are real and worth taking seriously. The crypto community is actively debating and working on solutions — including shifting mining operations toward renewable energy sources which is already happening at significant scale.

What Happens When All Bitcoin is Mined

There will only ever be 21 million Bitcoin. As of 2026 over 19 million have already been mined. The last Bitcoin is projected to be mined around the year 2140.

So what happens to miners when there are no more new Bitcoin to earn as rewards?

They earn transaction fees instead.

Every Bitcoin transaction includes a small fee paid to the miner who includes it in a block. Currently these fees are a secondary source of income for miners alongside the block reward. As the block reward decreases over time through a process called the halving — which cuts the reward in half approximately every four years — transaction fees are designed to gradually replace it as the primary miner incentive.

Whether transaction fees alone will be sufficient to sustain the mining ecosystem after 2140 is one of the most debated long term questions in Bitcoin economics. Most analysts believe that as Bitcoin adoption grows and transaction volume increases fees will be more than sufficient. But it remains an open question that the crypto community will be debating for decades to come.

Who Are the Miners?

In 2010 Laszlo Hanyecz could mine Bitcoin profitably using a standard laptop. Those days are long gone.

Today Bitcoin mining is dominated by large industrial operations — warehouses filled with thousands of specialised computers called ASICs running around the clock in locations chosen for cheap electricity and cool climates. Iceland, Kazakhstan, the United States and parts of China have all been major mining hubs at various points for exactly these reasons.

Individual mining of Bitcoin is no longer economically viable for most people due to the enormous upfront cost of equipment and the ongoing electricity costs. However mining pools — where thousands of individual miners combine their computing power and share the rewards proportionally — allow smaller participants to earn steady if modest income from mining.

Other cryptocurrencies that use Proof of Work but have less mining competition can still be mined profitably with consumer hardware in some cases though the landscape changes constantly as more miners enter and leave different networks.

The Bigger Picture

Laszlo Hanyecz spent 10,000 Bitcoin on pizza because he understood something most people at the time did not — that those coins had been earned by real work. His computer had spent real time and consumed real electricity solving real puzzles to earn them.

That is what gives mined cryptocurrency a form of tangible foundation that purely printed money lacks. Every Bitcoin in existence was earned through computational work. Nobody created it from nothing with a printing press. It was mined — the same way gold is mined — through effort, energy and competition.

Whether that makes Bitcoin valuable enough to justify its energy consumption is a debate that will continue for years. But understanding why mining exists and how it works puts you in a far better position to form your own informed opinion about it.

If you could go back to 2010 and mine Bitcoin with a laptop would you have done it — or would you have been too sceptical to try? Drop your answer in the comments — I read and reply to every one.