OP_RETURN: Bitcoin's On-Chain Data Mechanism
OP_RETURN embeds arbitrary data in Bitcoin transactions without touching the UTXO set. The mechanism, relay policy distinctions, and where developers go wrong.
№ 002BitcoinCoin Age: The Metric That Shaped Early Proof-of-Stake
Coin age powered the first proof-of-stake blockchains before being quietly retired. It had genuine appeal and a structural flaw that slashing eventually solved.
№ 003BitcoinBitcoin's Coinbase Maturity Rule Explained
Bitcoin forces miners to wait 100 blocks before spending a block reward. Here's the exact mechanic, why it exists, and what it prevents.
№ 004BitcoinHow Bitcoin's UTXO Model Prevents Double Spending
Bitcoin stops double spending without a bank using unspent transaction outputs. Here's the exact mechanism, with a worked example.