What is Bitcoin (BTC)?

Bitcoin (BTC) is the world's first and largest cryptocurrency (digital money that lives on the internet, with no bank or government in charge). It is a kind of online cash that anyone, anywhere, can send to anyone else without asking permission from a company or a bank. Bitcoin runs on a public, shared record called a blockchain, and today it is the #1 cryptocurrency by market value.

What is Bitcoin in simple terms?

Imagine a giant notebook that everyone in the world can read, but no single person can secretly erase or rewrite. Every time someone sends Bitcoin, a new line is added to that notebook for all to see. That shared notebook is the blockchain (a chain of "blocks," where each block is a page of recent transactions). Because thousands of computers around the world keep their own identical copy, no one can cheat the records without everyone noticing.

Regular money you keep in a bank is controlled by that bank: it can freeze your account or block a payment. Bitcoin works differently. It is decentralized (no boss, no head office, no single owner). Instead, the network is run by many people and computers together. That is the big idea behind what is Bitcoin: money that belongs to its users, not to a company.

Who created Bitcoin and when?

Bitcoin was created by a person (or group) using the fake name Satoshi Nakamoto. In October 2008, Satoshi published a short document called the Bitcoin whitepaper (a plan explaining how the system would work). On January 3, 2009, the very first block of the blockchain — the "genesis block" — was created, and Bitcoin officially came to life.

This happened soon after the 2008 global financial crisis, when many people had lost trust in banks. Satoshi wanted a form of money that did not depend on banks or governments. To this day, no one knows who Satoshi Nakamoto really is. After helping build the project for a couple of years, Satoshi quietly disappeared around 2010–2011 and has not been heard from since. The project kept going because the software is open source (the code is public, so anyone can read it, check it, and help improve it).

How does Bitcoin work?

Here is how Bitcoin works, step by step, in plain words:

• You hold a "wallet." A Bitcoin wallet is an app that stores your secret key (a long password that proves the coins are yours). Whoever holds the key controls the coins.
• You send a transaction. When you pay someone, your wallet announces it to the whole network: "I am sending this amount of BTC to that person."
• Computers check it. Special computers called miners gather up recent transactions and make sure no one is trying to spend coins they don't have.
• A block is added. Roughly every 10 minutes, the verified transactions are bundled into a new block and locked onto the blockchain forever.
• It cannot be undone. Once written, a transaction is permanent — like writing in pen, not pencil.

The process that adds new blocks is called mining. Miners run powerful computers that compete to solve a hard math puzzle. The first to solve it gets to add the next block and earns a reward in brand-new bitcoins. This system is called Proof of Work (you have to do real, costly computer work to be trusted), and it is what keeps the network honest and very hard to attack.

What makes Bitcoin different?

Lots of cryptocurrencies exist now, but Bitcoin stands apart for a few reasons:

• It was first. Bitcoin started the entire crypto industry. Everything else came after it.
• Its supply is limited. There will only ever be 21 million bitcoins — no more can be created. Because it is scarce like gold, many people call Bitcoin "digital gold."
• "Halving" slows new supply. About every four years, the reward miners earn for each block is cut in half. This event, called the halving, gradually reduces how many new bitcoins appear, which is built right into the rules.
• It is the most secure. Because so many computers protect it, the Bitcoin network has never been hacked in its core record.

This mix of being scarce, predictable, and very hard to control is the heart of Bitcoin explained in one breath: a money supply that no person or government can secretly inflate.

What is Bitcoin used for?

BTC is used in a few main ways:

• A store of value. Many people buy and hold Bitcoin hoping it keeps or grows its value over time, similar to how others hold gold. In the crypto world, holding for the long term is jokingly called "HODLing."
• Sending money across the world. You can send BTC to someone in another country in minutes, without going through a bank, at any hour of any day.
• Payments. Some businesses accept Bitcoin directly, and the Lightning Network (a faster, cheaper add-on built on top of Bitcoin) makes small everyday payments quick and low-cost.

It is worth knowing that Bitcoin is not anonymous. Every transaction is public on the blockchain. Your name isn't written there, but the trail of payments is visible to everyone, like a license plate you can follow even if you don't know the driver's name.

How do you buy and store Bitcoin (BTC)?

You can buy Bitcoin on a crypto exchange (a website or app where people trade crypto, such as a regulated marketplace in your country). You usually create an account, prove your identity, connect your bank card or transfer, and then buy as much or as little BTC as you want — you don't need to buy a whole coin, since each bitcoin can be split into tiny pieces (the smallest unit is called a satoshi).

Once you own BTC, you choose where to keep it:

• Hot wallet: an app on your phone or computer that is connected to the internet. Convenient, but a bit more exposed to hackers.
• Cold wallet: a small offline device (also called a hardware wallet). Safer for larger amounts because it stays disconnected from the internet.

The golden rule: whoever controls the secret key controls the coins. Never share your secret words (your "seed phrase") with anyone, and never type them into a website. If you lose them, no support team can recover your Bitcoin for you.

Is Bitcoin safe? Risks to know

The Bitcoin network itself is very secure and has run nonstop since 2009. But owning BTC still carries real risks you should understand:

• Price swings. Bitcoin's value can rise or fall sharply in a single day. It can be a bumpy ride.
• Scams and theft. The technology is safe, but fake "support" agents, phishing links, and bogus giveaways try to trick people into handing over their keys.
• No undo button. If you send BTC to the wrong address, it is usually gone for good. Double-check before you send.
• Lost keys. Lose your secret words and you lose access to your coins permanently.

None of this is financial advice — always do your own research and only ever use money you can afford to risk.

Frequently asked questions about Bitcoin (BTC)

Is Bitcoin real money?

Bitcoin is digital money you can send and receive worldwide, and some businesses accept it as payment. Unlike dollars or euros, no government issues or backs it; its value comes from what people are willing to pay and from its limited supply.

How many bitcoins are there?

There will only ever be 21 million bitcoins. New ones are released slowly through mining, and the amount created keeps shrinking through events called halvings. A large majority have already been mined.

Can Bitcoin be hacked?

The core Bitcoin network has never been hacked, thanks to thousands of computers protecting it. Most losses happen when individuals get tricked into revealing their secret keys or use unsafe websites — so protecting your own wallet is the most important step.

Do I have to buy a whole bitcoin?

No. Each bitcoin splits into 100 million tiny units called satoshis, so you can buy a small fraction — for example, a few dollars' worth — and still own real BTC.