비트코인은 어떻게 작동하나요?
비트코인은 인터넷 현금이라고 생각하면 됩니다. 2008년에 세상에 소개되어 몇 달 후인 2009년에 출시된 최초의 디지털 화폐입니다. 이를 이용하면 중개자 없이 다른 사람에게 직접 돈을 보낼 수 있습니다.
Bitcoin is the first virtual asset in history. It was introduced through a whitepaper in 2008 and officially launched in January 2009. The creator is known only by the pseudonym Satoshi Nakamoto.
- It operates on blockchain technology, which serves as a public ledger. Instead of banks verifying transactions, a global network of computers performs this task.
- No specific company or government owns it. It features decentralization, transparency, and open-source characteristics, serving as an alternative to the traditional financial system.
What is Bitcoin?
Think of Bitcoin as internet cash. It is the first digital currency, introduced to the world in 2008 and launched a few months later in 2009. It allows you to send money directly to others without intermediaries.
Note that we usually use the uppercase 'B' for 'Bitcoin' when referring to the network or technology, and the lowercase 'b' for 'bitcoin' when referring to the coin itself. The ticker symbol you see on exchanges is BTC.
Unlike dollars or euros in your wallet that are issued and controlled by governments, Bitcoin is decentralized. This means there is no single administrator, bank, or government running the Bitcoin network. It is a strictly P2P (peer-to-peer) system.
Why do people like Bitcoin? Because they can own and control their own money. They can send money anywhere, anytime without relying on intermediaries. Also, the system is immune to double-spending attacks, meaning one cannot attempt to use a coin in another place after spending it once.
How does Bitcoin work?
Bitcoin relies on a technology called the blockchain. You can think of the blockchain as a digital notebook that anyone can read but no one can erase.
Every transaction is recorded in a 'block' as it happens. That block connects to the previous block, forming a chain. This record is copied across thousands of computers (nodes) worldwide.
Since so many computers hold a copy of the notebook, no one can cheat. If someone tries to manipulate the ledger to give themselves more money, the other computers will reject it. Also, anyone can download Bitcoin's open-source software to participate in the ecosystem.
- Decentralization: The Bitcoin blockchain is maintained by a distributed computer network, so no central authority controls the ledger.
- Immutability: Once a transaction is added to the blockchain, it cannot be changed or deleted.
- Security: Transactions are protected by cryptographic technology, and verifying each block requires significant resources and repetitive work (solving puzzles through a process called mining).
Example of a BTC Transaction
Technically, Bitcoin does not use bank accounts with balances. Instead, it uses a system called UTXO (Unspent Transaction Output) which tracks individual digital coins in a wallet. However, to help you understand, let's look at it like a bank transfer.
Suppose Alice wants to send 1 BTC to Bob. The blockchain updates to show Alice decreasing by 1 BTC and Bob increasing by 1 BTC. This is similar to Alice writing "I gave Bob 1 bitcoin" on a public bulletin board so everyone knows the money moved.
Later, if Bob wants to send that money to Carol, the network checks the records to verify that Bob actually received the money from Alice. Because the computers constantly communicate with each other, everyone's ledger stays synchronized.
Bitcoin Mining
Mining is how the network secures itself and how new bitcoins come into existence. When you broadcast a transaction, it propagates across the network. Then, users called miners gather these transactions into a block.
To add this block to the blockchain, miners must solve a specific puzzle. The miner who solves the puzzle first adds the block and receives new bitcoins as a reward. This reward is the only way new bitcoins are created.
However, the supply is limited. Bitcoin will never exceed 21 million coins. Once all 21 million are mined (estimated around the year 2140), miners will no longer receive block rewards and will only be rewarded by transaction fees paid by users.
Proof of Work (PoW) and Energy Consumption
To maintain the security and integrity of the blockchain, Bitcoin uses a consensus mechanism called Proof of Work (PoW). This is a core part of the mining process explained earlier.
PoW is a mechanism created alongside Bitcoin to prevent double-spending in digital payment systems. Besides Bitcoin, many virtual assets use PoW to secure their blockchain networks.
The 'puzzle' miners must solve essentially refers to PoW. It is designed so that creating a block is expensive, but verifying its validity is cheap. If someone tries to cheat with an invalid block, the network rejects it immediately, and the miner cannot recover the mining cost.
PoW requires significant computing power and thus consumes a lot of electricity. This has led to debates about Bitcoin's environmental impact. However, in recent years, the mining industry has shifted significantly towards using renewable energy or wasted surplus energy.
Where is Bitcoin used?
Bitcoin is primarily used as digital currency and a store of value. You can use it like traditional currency to purchase goods online or offline. From online shopping malls to offline stores, more and more businesses are accepting Bitcoin as a payment method.
The main Bitcoin network (Layer 1) can be slow or expensive for small payments, but 'Layer 2' solutions like the Lightning Network have been developed to address these limitations.
From an investment perspective, many people buy BTC expecting its value to rise. While Bitcoin's price can be volatile, some investors view it as a way to diversify their portfolio and hedge against inflation over the long term.
Who created Bitcoin?
Bitcoin first appeared in October 2008 when Satoshi Nakamoto published a whitepaper titled "Bitcoin: A Peer-to-Peer Electronic Cash System." This paper introduced a new digital currency that operates in a decentralized system without relying on governments or banking systems.
In January 2009, the Bitcoin protocol officially started with the mining of the 'Genesis Block.' The first Bitcoin transaction took place between Satoshi Nakamoto and programmer Hal Finney. It was a transaction where Nakamoto sent 10 bitcoins to Finney.
After this first transaction, more people discovered Bitcoin and started participating in the network. It gained popularity among small tech enthusiast communities by proving that this digital currency could function without central authorities or intermediaries.
'Bitcoin Pizza' is another important milestone in Bitcoin history, being the first instance where Bitcoin was used as an exchange medium for real-world trade. On May 22, 2010, a programmer named Laszlo Hanyecz made history by buying two pizzas for 10,000 bitcoins. This transaction became known as 'Bitcoin Pizza Day' and is still celebrated every year on May 22nd.
Who is Satoshi Nakamoto?
The identity of Satoshi Nakamoto remains a mystery. Satoshi could be an individual or a group of developers located anywhere in the world. The name is Japanese, but many believe they are likely from an English-speaking country because of their highly fluent English. Despite many theories and investigations over the years, the true identity of the creator has not been revealed.
Did Satoshi invent blockchain technology?
Bitcoin combines several existing technologies that have existed for a long time, including blockchain technology. The use of immutable data structures dates back to the early 1990s when Stuart Haber and W. Scott Stornetta proposed a time-stamping system for documents.
Bitcoin also uses Merkle Trees, a concept developed by Ralph Merkle. Like today's blockchains, these early systems also relied on cryptographic technology to protect data and prevent tampering. However, Bitcoin was revolutionary because it combined these technologies to solve the double-spending problem that plagued other digital payment systems at the time.
How much Bitcoin is there?
The protocol has set the maximum supply of Bitcoin at 21 million coins. As of January 2026, over 95% of this has been mined, but it will take over 100 years to produce the rest. This is due to a periodic event called the 'Bitcoin halving,' which reduces the mining reward approximately every four years.
What is the Bitcoin Halving?
The Bitcoin halving refers to a periodic event where the block reward provided to miners is cut in half. The next Bitcoin halving is expected to occur in 2028, approximately four years after the last halving which took place on April 19, 2024.
The Bitcoin halving is central to the economic model. It ensures coins are issued at a steady rate and increases mining difficulty at a predictable rate. This controlled monetary inflation rate is essentially one of the main differences between Bitcoin and traditional fiat currencies, which can be supplied infinitely.
Is Bitcoin safe?
One of the major risks associated with Bitcoin is the possibility of hacking and theft. For example, in phishing scams, hackers use social engineering to trick users into revealing login information or private keys. If a hacker gains access to a user's account or crypto wallet, they can transfer the victim's bitcoins to their own wallet.
Another way hackers steal Bitcoin is through malware or ransomware attacks. A hacker can infect a user's computer or mobile device with malware to access the Bitcoin wallet. In some cases, ransomware is used to encrypt a user's files and demand Bitcoin in exchange for unlocking them.
Since Bitcoin transactions are irreversible and are not guaranteed by government agencies, users must take precautions to protect their assets. This includes using strong passwords, enabling two-factor authentication (2FA), and using 'cold storage' or hardware wallets (devices that keep keys offline) to keep funds out of reach from online hackers. It is also important to only download Bitcoin-related software from trusted sources.
Another risk associated with Bitcoin is price volatility. Bitcoin's value can fluctuate significantly in a short period, making it a risky investment for those unprepared for price surges and potential losses. However, historically volatility has tended to decrease as the asset matures and market liquidity increases.
Conclusion
Bitcoin has come a long way from its humble beginnings, growing into a globally recognized asset based on numerous use cases and increasing institutional adoption. Whether for daily transactions, short-term trading, long-term investment, or simply an interest in the technology, Bitcoin is certainly worth exploring further.
