Why couldn’t digital cash succeed before Bitcoin? The biggest hurdle was the “Double-Spend Problem”.
Unlike cash in your hand—where giving a banknote to someone means you no longer have it—digital files (like pictures or documents) can be copied endlessly.
💡 How Bitcoin Solves Double-Spending
Instead of trusting a central server to verify whether you still have the money, Bitcoin uses a public ledger that records transactions sequentially. If someone tries to spend the same coin twice, the network rejects the duplicate transaction because the ledger shows the coin has already been spent.
🧠 Today's Key Takeaway
- Digital files are easy to copy, creating a double-spending risk for digital money.
- Bitcoin prevents double-spending through a consensus-backed sequential ledger.
