Capitalizations Index – B ∞/21M
A cold wallet stores bitcoin offline, keeping private keys away from internet threats. It uses hardware devices, paper backups, or air-gapped systems to provide strong protection against hacks and theft.
bitcoin can be lost: without access to private keys or if sent to a wrong or unspendable address, coins are irretrievable on the blockchain. Secure backups and address verification prevent loss.
A 51% attack happens when an entity controls over half of a blockchain’s mining/hashing power, allowing double-spends, transaction censorship, and chain reorganizations that compromise network integrity.
bitcoin is a decentralized digital currency enabling peer-to-peer transfers without intermediaries, secured by blockchain and cryptography, offering transparency, limited supply, and programmable transactions.
bitcoin’s protocol is cryptographically robust and blockchain consensus prevents double-spending. True security depends on protecting private keys: loss or theft hands attackers full control of funds.
Proof of Work requires miners to solve difficult cryptographic puzzles to add blocks and confirm transactions. bitcoin uses PoW so altering history becomes computationally impractical.
Learn how to start using bitcoin today: set up a secure wallet, choose a trusted exchange to buy BTC, verify your identity, and make transactions. Tips on fees, security, and confirmation.
Multisig (multi-signature) requires multiple private keys to authorize bitcoin transactions, enhancing security and enabling shared custody, escrow, and corporate wallets without relying on a single signer.