Bitcoin currently verifies digital transaction signatures using the classical cryptographic algorithms ECDSA and Schnorr, which existing non-quantum computers are unable to reverse-engineer

The first and largest cryptocurrency, spanning its price and adoption, mining, protocol politics, and its contested role as digital money and inflation hedge.

How changes to Bitcoin's rules get proposed, fought over and adopted, from improvement proposals and soft forks to upgrade debates like quantum resistance.

Mathematical foundations of blockchains: hash functions, digital signatures, and encryption schemes that secure transactions, wallets, and consensus.