How does cryptocurrency work?
Bitcoin is the first and most well-known, but there are thousands of types of cryptocurrencies. Many, like Litecoin and Bitcoin Cash, share Bitcoin’s core characteristics but explore new ways to process transactions. Others offer a wider range of features. Ethereum, for example, can be used to run applications and create contracts. All four, however, are based on an idea called the blockchain, which is key to understanding how cryptocurrency works.
At its most basic, a blockchain is a list of transactions that anyone can view and verify. The Bitcoin blockchain, for example, is a record of every time someone sends or receives bitcoin. This list of transactions is fundamental for most cryptocurrencies because it enables secure payments to be made between people who don’t know each other without having to go through a third-party verifier like a bank.
Blockchain technology is also exciting because it has many uses beyond cryptocurrency. Blockchains are being used to explore medical research, improve the sharing of healthcare records, streamline supply chains, increase privacy on the internet, and so much more.
The principles behind both bitcoin and the Bitcoin blockchain first appeared online in a white-paper published in late 2007 by a person or group going by the name Satoshi Nakamoto.
The blockchain ledger is split across all the computers on the network, which are constantly verifying that the blockchain is accurate.This means there is no central vault, entity, or database that can be hacked, stolen, or manipulated.
Key concept
Cryptocurrencies use a technology called public-private key cryptography to transfer coin ownership on a secure and distributed ledger. A private key is an ultra secure password that never needs to be shared with anyone, with which you can send value on the network. An associated public key can be freely and safely shared with others to receive value on the network. From the public key, it is impossible for anyone to guess your private key.
What is cryptocurrency mining?
Most cryptocurrencies are ‘mined’ via a decentralized (also known as peer-to-peer) network of computers. But mining doesn’t just generate more bitcoin or Ethereum - it’s also the mechanism that updates and secures the network by constantly verifying the public blockchain ledger and adding new transactions.
Technically, anyone with a computer and an internet connection can become a miner. But before you get excited, it’s worth noting that mining is not always profitable. Depending on which cryptocurrency you’re mining, how fast your computer is, and the cost of electricity in your area, you may end up spending more on mining than you earn back in cryptocurrency.
As a result, most crypto mining these days is done by companies that specialize in it, or by large groups of individuals who all contribute their computing power.
How does the network encourage miners to participate in maintaining the blockchain? Again, taking Bitcoin as an example, the network holds a lottery in which all the mining rigs around the world race to become the first to solve a math problem, which also verifies and updates the blockchain with new transactions. Each winner is awarded new bitcoin, which can then make its way into the broader marketplace.
Key question
Where do cryptocurrencies get their value?
The economic value of cryptocurrency, like all goods and services, comes from supply and demand.
Supply refers to how much is available—like how many bitcoin are available to buy at any moment in time. Demand refers to people’s desire to own it—as in how many people want to buy bitcoin and how strongly they want it. The value of a cryptocurrency will always be a balance of both factors.
There are also other types of value. For example, there’s the value you get from using a cryptocurrency. Many people enjoy spending or gifting crypto, meaning that it gives them a sense of pride to support an exciting new financial system. Similarly, some people like to shop with bitcoin because they like its low fees and want to encourage businesses to accept it.
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