Wallet
Software or hardware that stores cryptographic keys and lets users send, receive, and interact with crypto assets. Wallets do not actually hold tokens — they hold the keys that control them on-chain.
What a wallet actually is
The technical reality:
- Wallet stores keys, not coins.
- Private key — secret that authorizes spending.
- Public key / address — receives funds.
- Coins exist on the blockchain, not in the wallet.
- Wallet is the interface for managing keys and signing transactions.
Lose the keys, lose access. The wallet itself is replaceable; the keys aren't.
Wallet types
Major categories:
- Hot wallet — connected to internet (browser, mobile, desktop).
- Cold wallet — offline storage.
- Hardware wallet — dedicated device (Ledger, Trezor).
- Software wallet — app-based (MetaMask, Phantom).
- Custodial wallet — exchange holds keys.
- Non-custodial wallet — user holds keys.
- Multisig — requires multiple signatures.
Each makes different trade-offs.
Custody spectrum
Several models:
- Self-custody — you control keys; full responsibility.
- Custodial — exchange or service holds keys; convenience and counterparty risk.
- Smart contract wallets — programmable custody (account abstraction).
- MPC wallets — distributed key management.
The convenience-vs-control trade-off has many points along the spectrum.
Common wallet mistakes
Frequent errors:
- Sharing seed phrase — never share with anyone.
- Photographing seed phrase — defeats the security model.
- Single backup location — losing the only backup is permanent loss.
- Wrong network — sending tokens to wrong chain often loses them.
- Approving malicious contracts — phishing attacks.
Wallet hygiene is critical to crypto safety.
Choosing a wallet
Considerations:
- Use case — daily spending, long-term holding, DeFi interaction.
- Chain support — does it support what you use?
- Track record — established wallets have fewer surprises.
- UX — varies dramatically.
- Hardware integration — for higher security.
Many users have multiple wallets for different purposes.
Backup and recovery
Critical practice:
- Seed phrase — write down, store securely.
- Multiple copies in geographically separated locations.
- Metal backups for fire/water resistance.
- Test recovery before relying on backup.
- Never digital — no photos, no cloud storage of seed.
Most lost crypto is due to backup failures.
Wallet security
Several practices:
- Hardware wallet for significant holdings.
- Separate wallets by purpose (savings, daily, DeFi).
- Verify addresses before sending.
- Review contract approvals periodically.
- Be skeptical of all unsolicited contact about your wallet.
Security is a continuous practice, not one-time setup.
What individuals should know
For all crypto users:
- Seed phrase is everything — protect accordingly.
- Self-custody requires real responsibility.
- Hardware wallets for any meaningful amount.
- Approve cautiously — most hacks involve user-signed malicious approvals.
Wallets are the foundation of crypto interaction. Understanding the security model and practicing good hygiene is essential to avoiding the most-common ways people lose funds.