What is Bitcoin?
Updated on August 24, 2026 · by Alex
Bitcoin is a payment network and a digital asset that runs without any bank or company administering it. Its central feature is that the total quantity that will ever exist is fixed at 21 million units, and nobody can change that number.
It is a public ledger. Thousands of computers around the world keep a copy of the same list of transactions and agree every ten minutes on which version is the correct one. That agreement is the whole invention: it lets two strangers transfer value without a bank confirming the operation.
New units are issued as a reward to those contributing computing power to maintain the network — mining — and that reward halves roughly every four years. That is the halving. Issuance keeps shrinking until it stops around the year 2140, when 21 million bitcoin exist and not one more.
Because it stopped being a fringe subject. With the approval of spot ETFs in the United States, buying exposure to bitcoin became as simple as buying a stock, and institutional money that previously had neither the means nor the mandate to participate came in.
That shift had a consequence many people find uncomfortable: bitcoin behaves more and more like a risk asset. It rises when the market has appetite and falls when it loses it, and its correlation with the Nasdaq in stressed moments is high. The safe-haven thesis sits badly with the last decade of data.
Buying it for the narrative and discovering the volatility afterwards. Bitcoin has fallen more than 70% from its highs on several occasions, and each drawdown lasted months or years. Any position is sized around that, not around the last six months of the chart.
The second mistake is treating “crypto” as one thing. Bitcoin and the rest of the market have completely different designs, risks and reasons to exist. A stablecoin resembles bitcoin no more than a term deposit resembles a stock.
