Have you ever thought about it? Ultimately, there are only three things in this world: tangible matter, the energy that keeps everything running, and the information that describes both.

Currency? Simply put, it's just a special string of numbers. Humans invented it to record and score the flow of material wealth and energy.

**From Physical Objects to Symbols: How Did Currency Become Purely Digital?**

The earliest forms of money were physical objects—shells could be traded for salt, sheep for cloth. Later, gold and silver made their appearance; stable and scarce, they became hard currency. But notice, even with gold coins, the core is still the number engraved on them: 1 gram, 10 grams.

The real turning point was paper money. How much could a piece of paper be worth? What it represented was a promise of "how much gold I owe you"—a number of claims. From that moment, currency parted ways with physical matter and became a symbol of credit—essentially, just a number.

**Why Can Everything Be Priced with Numbers?**

In the modern economy, a house, a hot pot meal, an hour of programming work—these things are completely incomparable directly. A house is concrete and steel, hot pot is ingredients and calories, programming is mental labor.

But once you put a price on them: 3,000,000, 200, 500—they can instantly be placed on the same scale. Currency translates all kinds of materials and energy into a unified, calculable, and tradable digital language. The pulse of the economy is hidden in the addition, subtraction, multiplication, and division of these numbers.

**The Digital Currency Era: The Ledger Is Already On-Chain**

Now? Bank account balances, mobile payments, on-chain wallets—money has long ceased to be paper, or even just a line of 0s and 1s in a database. Blockchain technology has given these numbers tamper-proof attributes, and cryptocurrency has decentralized the "right to keep the ledger" from centralized institutions.

The ultimate form of money might look like this: a globally recognized digital system—transparent, efficient, and without intermediaries. From shells to Bitcoin, the essence has never changed—it's always been about using numbers to keep clear records for this world made of matter and energy.