Ledger LandISSUE #20 of 90

bitcoin · the first blockchain

BlockyVSDouble-Spend Dan

Blocky saysBitcoin was the first blockchain — digital scarcity and peer-to-peer money without banks.

Satoshi Nakamoto's 2009 Bitcoin solved double-spending without a central authority, creating the first provably scarce digital asset. Capped at 21 million coins, secured by Proof of Work, it's deliberately conservative: simple scripting, slow blocks (~10 min), maximal security and decentralization over speed. It established the entire field — every later chain reacts to its design choices.

Power-ups you unlock

First blockchain (2009), peer-to-peer money
Solved double-spend with no central authority
Capped supply (21M), PoW-secured
Conservative: security over speed

Double-Spend Dan attacks — common mistakes

Expecting Bitcoin to be fast or feature-rich
Confusing the asset (BTC) with the network
Assuming later chains improved on every axis

Boss battleName the one problem Bitcoin solved that prior digital cash could not.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>before: digital cash could be copied (double-spent)
Bitcoin: PoW + chain → provable scarcity, no bank
21M cap · ~10 min blocks · security first</pre></body></html>

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