What is Bitcoin

Bitcoin is a public list of payments that anyone can check and nobody can edit after the fact. The software shipped in 2009. The unit people trade is the bitcoin, and the ticker is BTC. There is no company that issues the coins and no bank that keeps the balances. The balances live on the ledger. A holder proves control with a key, which is the part a wallet is for.

New bitcoins are created when a miner adds a block. The network aims for a block about every ten minutes. The miner who adds it is paid a fixed number of new coins plus the fees in that block. The reward is cut in half on a schedule. That cut is the halving. The supply is capped at 21 million coins, and the cap is in the software, not in a press release. Litecoin, which this desk marked at 15 years, copied the idea and changed the numbers. That anniversary is here: https://cryptokeymedia.com/news/litecoin-15-years

A bitcoin and a claim on a bitcoin are not the same object. A coin in a wallet the holder controls can be sent. A coin on an exchange is an entry in the exchange's books. A wrapped token such as wBTC or cbBTC is a receipt on another chain. A spot ETF share is a fund share that tracks the price. A perpetual is a bet on the price with no coin delivered. Each of those can move when the bitcoin price moves. Only one of them is the coin.

The dollar price is what a buyer last paid. It is not the value of the network, and it is not the market cap. Market cap is the price times the coins already issued. A one percent move in the price moves the market cap by one percent. The supply does not have to change for the headline number to change. Quoting the price and quoting the market cap as if they were one figure is the mistake.

The chain does not close. Blocks arrive overnight, on weekends, and on market holidays. That is why a desk can print a bitcoin number when the stock market is shut, and why a stock token that tracks Apple still has to wait for the Nasdaq open to find out what the share did. Bitcoin does not have that wait. The next block is the clock.

Sending one requires an address and a fee. The fee is bid by the sender. When a lot of people want the next block, the fee rises. When the queue is empty, it falls. The fee is not a tax set by a company. It is the price of space in the block. A transfer that underpays can sit. A transfer that pays the going rate is the one miners take.

Nothing in the design promises a return. The cap limits how many coins can exist. It does not say what a coin will be worth next month. Miners can sell the coins they earn. Holders can sell the coins they bought. The price is the meeting of those sales. A page that shows the price is a quote. It is not a forecast, and this desk does not add one.

What comes next is the next block, and then the next halving already on the calendar. The coins outstanding rise a little with every block until the reward is cut again. The price will move on its own clock. The definition does not. Bitcoin is the ledger, the capped supply, and the coin a key can spend.